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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/x86/kernel/cpu/mtrr
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/kernel/cpu/mtrr')
-rw-r--r--arch/x86/kernel/cpu/mtrr/Makefile4
-rw-r--r--arch/x86/kernel/cpu/mtrr/amd.c125
-rw-r--r--arch/x86/kernel/cpu/mtrr/centaur.c127
-rw-r--r--arch/x86/kernel/cpu/mtrr/cleanup.c987
-rw-r--r--arch/x86/kernel/cpu/mtrr/cyrix.c284
-rw-r--r--arch/x86/kernel/cpu/mtrr/generic.c924
-rw-r--r--arch/x86/kernel/cpu/mtrr/if.c425
-rw-r--r--arch/x86/kernel/cpu/mtrr/mtrr.c887
-rw-r--r--arch/x86/kernel/cpu/mtrr/mtrr.h80
9 files changed, 3843 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/mtrr/Makefile b/arch/x86/kernel/cpu/mtrr/Makefile
new file mode 100644
index 000000000..cc4f9f1cb
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-y := mtrr.o if.o generic.o cleanup.o
+obj-$(CONFIG_X86_32) += amd.o cyrix.o centaur.o
+
diff --git a/arch/x86/kernel/cpu/mtrr/amd.c b/arch/x86/kernel/cpu/mtrr/amd.c
new file mode 100644
index 000000000..a65a02720
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/amd.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <asm/mtrr.h>
+#include <asm/msr.h>
+
+#include "mtrr.h"
+
+static void
+amd_get_mtrr(unsigned int reg, unsigned long *base,
+ unsigned long *size, mtrr_type *type)
+{
+ unsigned long low, high;
+
+ rdmsr(MSR_K6_UWCCR, low, high);
+ /* Upper dword is region 1, lower is region 0 */
+ if (reg == 1)
+ low = high;
+ /* The base masks off on the right alignment */
+ *base = (low & 0xFFFE0000) >> PAGE_SHIFT;
+ *type = 0;
+ if (low & 1)
+ *type = MTRR_TYPE_UNCACHABLE;
+ if (low & 2)
+ *type = MTRR_TYPE_WRCOMB;
+ if (!(low & 3)) {
+ *size = 0;
+ return;
+ }
+ /*
+ * This needs a little explaining. The size is stored as an
+ * inverted mask of bits of 128K granularity 15 bits long offset
+ * 2 bits.
+ *
+ * So to get a size we do invert the mask and add 1 to the lowest
+ * mask bit (4 as its 2 bits in). This gives us a size we then shift
+ * to turn into 128K blocks.
+ *
+ * eg 111 1111 1111 1100 is 512K
+ *
+ * invert 000 0000 0000 0011
+ * +1 000 0000 0000 0100
+ * *128K ...
+ */
+ low = (~low) & 0x1FFFC;
+ *size = (low + 4) << (15 - PAGE_SHIFT);
+}
+
+/**
+ * amd_set_mtrr - Set variable MTRR register on the local CPU.
+ *
+ * @reg The register to set.
+ * @base The base address of the region.
+ * @size The size of the region. If this is 0 the region is disabled.
+ * @type The type of the region.
+ *
+ * Returns nothing.
+ */
+static void
+amd_set_mtrr(unsigned int reg, unsigned long base, unsigned long size, mtrr_type type)
+{
+ u32 regs[2];
+
+ /*
+ * Low is MTRR0, High MTRR 1
+ */
+ rdmsr(MSR_K6_UWCCR, regs[0], regs[1]);
+ /*
+ * Blank to disable
+ */
+ if (size == 0) {
+ regs[reg] = 0;
+ } else {
+ /*
+ * Set the register to the base, the type (off by one) and an
+ * inverted bitmask of the size The size is the only odd
+ * bit. We are fed say 512K We invert this and we get 111 1111
+ * 1111 1011 but if you subtract one and invert you get the
+ * desired 111 1111 1111 1100 mask
+ *
+ * But ~(x - 1) == ~x + 1 == -x. Two's complement rocks!
+ */
+ regs[reg] = (-size >> (15 - PAGE_SHIFT) & 0x0001FFFC)
+ | (base << PAGE_SHIFT) | (type + 1);
+ }
+
+ /*
+ * The writeback rule is quite specific. See the manual. Its
+ * disable local interrupts, write back the cache, set the mtrr
+ */
+ wbinvd();
+ wrmsr(MSR_K6_UWCCR, regs[0], regs[1]);
+}
+
+static int
+amd_validate_add_page(unsigned long base, unsigned long size, unsigned int type)
+{
+ /*
+ * Apply the K6 block alignment and size rules
+ * In order
+ * o Uncached or gathering only
+ * o 128K or bigger block
+ * o Power of 2 block
+ * o base suitably aligned to the power
+ */
+ if (type > MTRR_TYPE_WRCOMB || size < (1 << (17 - PAGE_SHIFT))
+ || (size & ~(size - 1)) - size || (base & (size - 1)))
+ return -EINVAL;
+ return 0;
+}
+
+static const struct mtrr_ops amd_mtrr_ops = {
+ .vendor = X86_VENDOR_AMD,
+ .set = amd_set_mtrr,
+ .get = amd_get_mtrr,
+ .get_free_region = generic_get_free_region,
+ .validate_add_page = amd_validate_add_page,
+ .have_wrcomb = positive_have_wrcomb,
+};
+
+int __init amd_init_mtrr(void)
+{
+ set_mtrr_ops(&amd_mtrr_ops);
+ return 0;
+}
diff --git a/arch/x86/kernel/cpu/mtrr/centaur.c b/arch/x86/kernel/cpu/mtrr/centaur.c
new file mode 100644
index 000000000..f27177816
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/centaur.c
@@ -0,0 +1,127 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/init.h>
+#include <linux/mm.h>
+
+#include <asm/mtrr.h>
+#include <asm/msr.h>
+
+#include "mtrr.h"
+
+static struct {
+ unsigned long high;
+ unsigned long low;
+} centaur_mcr[8];
+
+static u8 centaur_mcr_reserved;
+static u8 centaur_mcr_type; /* 0 for winchip, 1 for winchip2 */
+
+/**
+ * centaur_get_free_region - Get a free MTRR.
+ *
+ * @base: The starting (base) address of the region.
+ * @size: The size (in bytes) of the region.
+ *
+ * Returns: the index of the region on success, else -1 on error.
+ */
+static int
+centaur_get_free_region(unsigned long base, unsigned long size, int replace_reg)
+{
+ unsigned long lbase, lsize;
+ mtrr_type ltype;
+ int i, max;
+
+ max = num_var_ranges;
+ if (replace_reg >= 0 && replace_reg < max)
+ return replace_reg;
+
+ for (i = 0; i < max; ++i) {
+ if (centaur_mcr_reserved & (1 << i))
+ continue;
+ mtrr_if->get(i, &lbase, &lsize, &ltype);
+ if (lsize == 0)
+ return i;
+ }
+
+ return -ENOSPC;
+}
+
+/*
+ * Report boot time MCR setups
+ */
+void mtrr_centaur_report_mcr(int mcr, u32 lo, u32 hi)
+{
+ centaur_mcr[mcr].low = lo;
+ centaur_mcr[mcr].high = hi;
+}
+
+static void
+centaur_get_mcr(unsigned int reg, unsigned long *base,
+ unsigned long *size, mtrr_type * type)
+{
+ *base = centaur_mcr[reg].high >> PAGE_SHIFT;
+ *size = -(centaur_mcr[reg].low & 0xfffff000) >> PAGE_SHIFT;
+ *type = MTRR_TYPE_WRCOMB; /* write-combining */
+
+ if (centaur_mcr_type == 1 && ((centaur_mcr[reg].low & 31) & 2))
+ *type = MTRR_TYPE_UNCACHABLE;
+ if (centaur_mcr_type == 1 && (centaur_mcr[reg].low & 31) == 25)
+ *type = MTRR_TYPE_WRBACK;
+ if (centaur_mcr_type == 0 && (centaur_mcr[reg].low & 31) == 31)
+ *type = MTRR_TYPE_WRBACK;
+}
+
+static void
+centaur_set_mcr(unsigned int reg, unsigned long base,
+ unsigned long size, mtrr_type type)
+{
+ unsigned long low, high;
+
+ if (size == 0) {
+ /* Disable */
+ high = low = 0;
+ } else {
+ high = base << PAGE_SHIFT;
+ if (centaur_mcr_type == 0) {
+ /* Only support write-combining... */
+ low = -size << PAGE_SHIFT | 0x1f;
+ } else {
+ if (type == MTRR_TYPE_UNCACHABLE)
+ low = -size << PAGE_SHIFT | 0x02; /* NC */
+ else
+ low = -size << PAGE_SHIFT | 0x09; /* WWO, WC */
+ }
+ }
+ centaur_mcr[reg].high = high;
+ centaur_mcr[reg].low = low;
+ wrmsr(MSR_IDT_MCR0 + reg, low, high);
+}
+
+static int
+centaur_validate_add_page(unsigned long base, unsigned long size, unsigned int type)
+{
+ /*
+ * FIXME: Winchip2 supports uncached
+ */
+ if (type != MTRR_TYPE_WRCOMB &&
+ (centaur_mcr_type == 0 || type != MTRR_TYPE_UNCACHABLE)) {
+ pr_warn("mtrr: only write-combining%s supported\n",
+ centaur_mcr_type ? " and uncacheable are" : " is");
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static const struct mtrr_ops centaur_mtrr_ops = {
+ .vendor = X86_VENDOR_CENTAUR,
+ .set = centaur_set_mcr,
+ .get = centaur_get_mcr,
+ .get_free_region = centaur_get_free_region,
+ .validate_add_page = centaur_validate_add_page,
+ .have_wrcomb = positive_have_wrcomb,
+};
+
+int __init centaur_init_mtrr(void)
+{
+ set_mtrr_ops(&centaur_mtrr_ops);
+ return 0;
+}
diff --git a/arch/x86/kernel/cpu/mtrr/cleanup.c b/arch/x86/kernel/cpu/mtrr/cleanup.c
new file mode 100644
index 000000000..b5f43049f
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/cleanup.c
@@ -0,0 +1,987 @@
+/*
+ * MTRR (Memory Type Range Register) cleanup
+ *
+ * Copyright (C) 2009 Yinghai Lu
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the Free
+ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/smp.h>
+#include <linux/cpu.h>
+#include <linux/mutex.h>
+#include <linux/uaccess.h>
+#include <linux/kvm_para.h>
+#include <linux/range.h>
+
+#include <asm/processor.h>
+#include <asm/e820/api.h>
+#include <asm/mtrr.h>
+#include <asm/msr.h>
+
+#include "mtrr.h"
+
+struct var_mtrr_range_state {
+ unsigned long base_pfn;
+ unsigned long size_pfn;
+ mtrr_type type;
+};
+
+struct var_mtrr_state {
+ unsigned long range_startk;
+ unsigned long range_sizek;
+ unsigned long chunk_sizek;
+ unsigned long gran_sizek;
+ unsigned int reg;
+};
+
+/* Should be related to MTRR_VAR_RANGES nums */
+#define RANGE_NUM 256
+
+static struct range __initdata range[RANGE_NUM];
+static int __initdata nr_range;
+
+static struct var_mtrr_range_state __initdata range_state[RANGE_NUM];
+
+static int __initdata debug_print;
+#define Dprintk(x...) do { if (debug_print) pr_debug(x); } while (0)
+
+#define BIOS_BUG_MSG \
+ "WARNING: BIOS bug: VAR MTRR %d contains strange UC entry under 1M, check with your system vendor!\n"
+
+static int __init
+x86_get_mtrr_mem_range(struct range *range, int nr_range,
+ unsigned long extra_remove_base,
+ unsigned long extra_remove_size)
+{
+ unsigned long base, size;
+ mtrr_type type;
+ int i;
+
+ for (i = 0; i < num_var_ranges; i++) {
+ type = range_state[i].type;
+ if (type != MTRR_TYPE_WRBACK)
+ continue;
+ base = range_state[i].base_pfn;
+ size = range_state[i].size_pfn;
+ nr_range = add_range_with_merge(range, RANGE_NUM, nr_range,
+ base, base + size);
+ }
+ if (debug_print) {
+ pr_debug("After WB checking\n");
+ for (i = 0; i < nr_range; i++)
+ pr_debug("MTRR MAP PFN: %016llx - %016llx\n",
+ range[i].start, range[i].end);
+ }
+
+ /* Take out UC ranges: */
+ for (i = 0; i < num_var_ranges; i++) {
+ type = range_state[i].type;
+ if (type != MTRR_TYPE_UNCACHABLE &&
+ type != MTRR_TYPE_WRPROT)
+ continue;
+ size = range_state[i].size_pfn;
+ if (!size)
+ continue;
+ base = range_state[i].base_pfn;
+ if (base < (1<<(20-PAGE_SHIFT)) && mtrr_state.have_fixed &&
+ (mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED) &&
+ (mtrr_state.enabled & MTRR_STATE_MTRR_FIXED_ENABLED)) {
+ /* Var MTRR contains UC entry below 1M? Skip it: */
+ pr_warn(BIOS_BUG_MSG, i);
+ if (base + size <= (1<<(20-PAGE_SHIFT)))
+ continue;
+ size -= (1<<(20-PAGE_SHIFT)) - base;
+ base = 1<<(20-PAGE_SHIFT);
+ }
+ subtract_range(range, RANGE_NUM, base, base + size);
+ }
+ if (extra_remove_size)
+ subtract_range(range, RANGE_NUM, extra_remove_base,
+ extra_remove_base + extra_remove_size);
+
+ if (debug_print) {
+ pr_debug("After UC checking\n");
+ for (i = 0; i < RANGE_NUM; i++) {
+ if (!range[i].end)
+ continue;
+ pr_debug("MTRR MAP PFN: %016llx - %016llx\n",
+ range[i].start, range[i].end);
+ }
+ }
+
+ /* sort the ranges */
+ nr_range = clean_sort_range(range, RANGE_NUM);
+ if (debug_print) {
+ pr_debug("After sorting\n");
+ for (i = 0; i < nr_range; i++)
+ pr_debug("MTRR MAP PFN: %016llx - %016llx\n",
+ range[i].start, range[i].end);
+ }
+
+ return nr_range;
+}
+
+#ifdef CONFIG_MTRR_SANITIZER
+
+static unsigned long __init sum_ranges(struct range *range, int nr_range)
+{
+ unsigned long sum = 0;
+ int i;
+
+ for (i = 0; i < nr_range; i++)
+ sum += range[i].end - range[i].start;
+
+ return sum;
+}
+
+static int enable_mtrr_cleanup __initdata =
+ CONFIG_MTRR_SANITIZER_ENABLE_DEFAULT;
+
+static int __init disable_mtrr_cleanup_setup(char *str)
+{
+ enable_mtrr_cleanup = 0;
+ return 0;
+}
+early_param("disable_mtrr_cleanup", disable_mtrr_cleanup_setup);
+
+static int __init enable_mtrr_cleanup_setup(char *str)
+{
+ enable_mtrr_cleanup = 1;
+ return 0;
+}
+early_param("enable_mtrr_cleanup", enable_mtrr_cleanup_setup);
+
+static int __init mtrr_cleanup_debug_setup(char *str)
+{
+ debug_print = 1;
+ return 0;
+}
+early_param("mtrr_cleanup_debug", mtrr_cleanup_debug_setup);
+
+static void __init
+set_var_mtrr(unsigned int reg, unsigned long basek, unsigned long sizek,
+ unsigned char type, unsigned int address_bits)
+{
+ u32 base_lo, base_hi, mask_lo, mask_hi;
+ u64 base, mask;
+
+ if (!sizek) {
+ fill_mtrr_var_range(reg, 0, 0, 0, 0);
+ return;
+ }
+
+ mask = (1ULL << address_bits) - 1;
+ mask &= ~((((u64)sizek) << 10) - 1);
+
+ base = ((u64)basek) << 10;
+
+ base |= type;
+ mask |= 0x800;
+
+ base_lo = base & ((1ULL<<32) - 1);
+ base_hi = base >> 32;
+
+ mask_lo = mask & ((1ULL<<32) - 1);
+ mask_hi = mask >> 32;
+
+ fill_mtrr_var_range(reg, base_lo, base_hi, mask_lo, mask_hi);
+}
+
+static void __init
+save_var_mtrr(unsigned int reg, unsigned long basek, unsigned long sizek,
+ unsigned char type)
+{
+ range_state[reg].base_pfn = basek >> (PAGE_SHIFT - 10);
+ range_state[reg].size_pfn = sizek >> (PAGE_SHIFT - 10);
+ range_state[reg].type = type;
+}
+
+static void __init set_var_mtrr_all(unsigned int address_bits)
+{
+ unsigned long basek, sizek;
+ unsigned char type;
+ unsigned int reg;
+
+ for (reg = 0; reg < num_var_ranges; reg++) {
+ basek = range_state[reg].base_pfn << (PAGE_SHIFT - 10);
+ sizek = range_state[reg].size_pfn << (PAGE_SHIFT - 10);
+ type = range_state[reg].type;
+
+ set_var_mtrr(reg, basek, sizek, type, address_bits);
+ }
+}
+
+static unsigned long to_size_factor(unsigned long sizek, char *factorp)
+{
+ unsigned long base = sizek;
+ char factor;
+
+ if (base & ((1<<10) - 1)) {
+ /* Not MB-aligned: */
+ factor = 'K';
+ } else if (base & ((1<<20) - 1)) {
+ factor = 'M';
+ base >>= 10;
+ } else {
+ factor = 'G';
+ base >>= 20;
+ }
+
+ *factorp = factor;
+
+ return base;
+}
+
+static unsigned int __init
+range_to_mtrr(unsigned int reg, unsigned long range_startk,
+ unsigned long range_sizek, unsigned char type)
+{
+ if (!range_sizek || (reg >= num_var_ranges))
+ return reg;
+
+ while (range_sizek) {
+ unsigned long max_align, align;
+ unsigned long sizek;
+
+ /* Compute the maximum size with which we can make a range: */
+ if (range_startk)
+ max_align = __ffs(range_startk);
+ else
+ max_align = BITS_PER_LONG - 1;
+
+ align = __fls(range_sizek);
+ if (align > max_align)
+ align = max_align;
+
+ sizek = 1UL << align;
+ if (debug_print) {
+ char start_factor = 'K', size_factor = 'K';
+ unsigned long start_base, size_base;
+
+ start_base = to_size_factor(range_startk, &start_factor);
+ size_base = to_size_factor(sizek, &size_factor);
+
+ Dprintk("Setting variable MTRR %d, "
+ "base: %ld%cB, range: %ld%cB, type %s\n",
+ reg, start_base, start_factor,
+ size_base, size_factor,
+ (type == MTRR_TYPE_UNCACHABLE) ? "UC" :
+ ((type == MTRR_TYPE_WRBACK) ? "WB" : "Other")
+ );
+ }
+ save_var_mtrr(reg++, range_startk, sizek, type);
+ range_startk += sizek;
+ range_sizek -= sizek;
+ if (reg >= num_var_ranges)
+ break;
+ }
+ return reg;
+}
+
+static unsigned __init
+range_to_mtrr_with_hole(struct var_mtrr_state *state, unsigned long basek,
+ unsigned long sizek)
+{
+ unsigned long hole_basek, hole_sizek;
+ unsigned long second_sizek;
+ unsigned long range0_basek, range0_sizek;
+ unsigned long range_basek, range_sizek;
+ unsigned long chunk_sizek;
+ unsigned long gran_sizek;
+
+ hole_basek = 0;
+ hole_sizek = 0;
+ second_sizek = 0;
+ chunk_sizek = state->chunk_sizek;
+ gran_sizek = state->gran_sizek;
+
+ /* Align with gran size, prevent small block used up MTRRs: */
+ range_basek = ALIGN(state->range_startk, gran_sizek);
+ if ((range_basek > basek) && basek)
+ return second_sizek;
+
+ state->range_sizek -= (range_basek - state->range_startk);
+ range_sizek = ALIGN(state->range_sizek, gran_sizek);
+
+ while (range_sizek > state->range_sizek) {
+ range_sizek -= gran_sizek;
+ if (!range_sizek)
+ return 0;
+ }
+ state->range_sizek = range_sizek;
+
+ /* Try to append some small hole: */
+ range0_basek = state->range_startk;
+ range0_sizek = ALIGN(state->range_sizek, chunk_sizek);
+
+ /* No increase: */
+ if (range0_sizek == state->range_sizek) {
+ Dprintk("rangeX: %016lx - %016lx\n",
+ range0_basek<<10,
+ (range0_basek + state->range_sizek)<<10);
+ state->reg = range_to_mtrr(state->reg, range0_basek,
+ state->range_sizek, MTRR_TYPE_WRBACK);
+ return 0;
+ }
+
+ /* Only cut back when it is not the last: */
+ if (sizek) {
+ while (range0_basek + range0_sizek > (basek + sizek)) {
+ if (range0_sizek >= chunk_sizek)
+ range0_sizek -= chunk_sizek;
+ else
+ range0_sizek = 0;
+
+ if (!range0_sizek)
+ break;
+ }
+ }
+
+second_try:
+ range_basek = range0_basek + range0_sizek;
+
+ /* One hole in the middle: */
+ if (range_basek > basek && range_basek <= (basek + sizek))
+ second_sizek = range_basek - basek;
+
+ if (range0_sizek > state->range_sizek) {
+
+ /* One hole in middle or at the end: */
+ hole_sizek = range0_sizek - state->range_sizek - second_sizek;
+
+ /* Hole size should be less than half of range0 size: */
+ if (hole_sizek >= (range0_sizek >> 1) &&
+ range0_sizek >= chunk_sizek) {
+ range0_sizek -= chunk_sizek;
+ second_sizek = 0;
+ hole_sizek = 0;
+
+ goto second_try;
+ }
+ }
+
+ if (range0_sizek) {
+ Dprintk("range0: %016lx - %016lx\n",
+ range0_basek<<10,
+ (range0_basek + range0_sizek)<<10);
+ state->reg = range_to_mtrr(state->reg, range0_basek,
+ range0_sizek, MTRR_TYPE_WRBACK);
+ }
+
+ if (range0_sizek < state->range_sizek) {
+ /* Need to handle left over range: */
+ range_sizek = state->range_sizek - range0_sizek;
+
+ Dprintk("range: %016lx - %016lx\n",
+ range_basek<<10,
+ (range_basek + range_sizek)<<10);
+
+ state->reg = range_to_mtrr(state->reg, range_basek,
+ range_sizek, MTRR_TYPE_WRBACK);
+ }
+
+ if (hole_sizek) {
+ hole_basek = range_basek - hole_sizek - second_sizek;
+ Dprintk("hole: %016lx - %016lx\n",
+ hole_basek<<10,
+ (hole_basek + hole_sizek)<<10);
+ state->reg = range_to_mtrr(state->reg, hole_basek,
+ hole_sizek, MTRR_TYPE_UNCACHABLE);
+ }
+
+ return second_sizek;
+}
+
+static void __init
+set_var_mtrr_range(struct var_mtrr_state *state, unsigned long base_pfn,
+ unsigned long size_pfn)
+{
+ unsigned long basek, sizek;
+ unsigned long second_sizek = 0;
+
+ if (state->reg >= num_var_ranges)
+ return;
+
+ basek = base_pfn << (PAGE_SHIFT - 10);
+ sizek = size_pfn << (PAGE_SHIFT - 10);
+
+ /* See if I can merge with the last range: */
+ if ((basek <= 1024) ||
+ (state->range_startk + state->range_sizek == basek)) {
+ unsigned long endk = basek + sizek;
+ state->range_sizek = endk - state->range_startk;
+ return;
+ }
+ /* Write the range mtrrs: */
+ if (state->range_sizek != 0)
+ second_sizek = range_to_mtrr_with_hole(state, basek, sizek);
+
+ /* Allocate an msr: */
+ state->range_startk = basek + second_sizek;
+ state->range_sizek = sizek - second_sizek;
+}
+
+/* Minimum size of mtrr block that can take hole: */
+static u64 mtrr_chunk_size __initdata = (256ULL<<20);
+
+static int __init parse_mtrr_chunk_size_opt(char *p)
+{
+ if (!p)
+ return -EINVAL;
+ mtrr_chunk_size = memparse(p, &p);
+ return 0;
+}
+early_param("mtrr_chunk_size", parse_mtrr_chunk_size_opt);
+
+/* Granularity of mtrr of block: */
+static u64 mtrr_gran_size __initdata;
+
+static int __init parse_mtrr_gran_size_opt(char *p)
+{
+ if (!p)
+ return -EINVAL;
+ mtrr_gran_size = memparse(p, &p);
+ return 0;
+}
+early_param("mtrr_gran_size", parse_mtrr_gran_size_opt);
+
+static unsigned long nr_mtrr_spare_reg __initdata =
+ CONFIG_MTRR_SANITIZER_SPARE_REG_NR_DEFAULT;
+
+static int __init parse_mtrr_spare_reg(char *arg)
+{
+ if (arg)
+ nr_mtrr_spare_reg = simple_strtoul(arg, NULL, 0);
+ return 0;
+}
+early_param("mtrr_spare_reg_nr", parse_mtrr_spare_reg);
+
+static int __init
+x86_setup_var_mtrrs(struct range *range, int nr_range,
+ u64 chunk_size, u64 gran_size)
+{
+ struct var_mtrr_state var_state;
+ int num_reg;
+ int i;
+
+ var_state.range_startk = 0;
+ var_state.range_sizek = 0;
+ var_state.reg = 0;
+ var_state.chunk_sizek = chunk_size >> 10;
+ var_state.gran_sizek = gran_size >> 10;
+
+ memset(range_state, 0, sizeof(range_state));
+
+ /* Write the range: */
+ for (i = 0; i < nr_range; i++) {
+ set_var_mtrr_range(&var_state, range[i].start,
+ range[i].end - range[i].start);
+ }
+
+ /* Write the last range: */
+ if (var_state.range_sizek != 0)
+ range_to_mtrr_with_hole(&var_state, 0, 0);
+
+ num_reg = var_state.reg;
+ /* Clear out the extra MTRR's: */
+ while (var_state.reg < num_var_ranges) {
+ save_var_mtrr(var_state.reg, 0, 0, 0);
+ var_state.reg++;
+ }
+
+ return num_reg;
+}
+
+struct mtrr_cleanup_result {
+ unsigned long gran_sizek;
+ unsigned long chunk_sizek;
+ unsigned long lose_cover_sizek;
+ unsigned int num_reg;
+ int bad;
+};
+
+/*
+ * gran_size: 64K, 128K, 256K, 512K, 1M, 2M, ..., 2G
+ * chunk size: gran_size, ..., 2G
+ * so we need (1+16)*8
+ */
+#define NUM_RESULT 136
+#define PSHIFT (PAGE_SHIFT - 10)
+
+static struct mtrr_cleanup_result __initdata result[NUM_RESULT];
+static unsigned long __initdata min_loss_pfn[RANGE_NUM];
+
+static void __init print_out_mtrr_range_state(void)
+{
+ char start_factor = 'K', size_factor = 'K';
+ unsigned long start_base, size_base;
+ mtrr_type type;
+ int i;
+
+ for (i = 0; i < num_var_ranges; i++) {
+
+ size_base = range_state[i].size_pfn << (PAGE_SHIFT - 10);
+ if (!size_base)
+ continue;
+
+ size_base = to_size_factor(size_base, &size_factor);
+ start_base = range_state[i].base_pfn << (PAGE_SHIFT - 10);
+ start_base = to_size_factor(start_base, &start_factor);
+ type = range_state[i].type;
+
+ pr_debug("reg %d, base: %ld%cB, range: %ld%cB, type %s\n",
+ i, start_base, start_factor,
+ size_base, size_factor,
+ (type == MTRR_TYPE_UNCACHABLE) ? "UC" :
+ ((type == MTRR_TYPE_WRPROT) ? "WP" :
+ ((type == MTRR_TYPE_WRBACK) ? "WB" : "Other"))
+ );
+ }
+}
+
+static int __init mtrr_need_cleanup(void)
+{
+ int i;
+ mtrr_type type;
+ unsigned long size;
+ /* Extra one for all 0: */
+ int num[MTRR_NUM_TYPES + 1];
+
+ /* Check entries number: */
+ memset(num, 0, sizeof(num));
+ for (i = 0; i < num_var_ranges; i++) {
+ type = range_state[i].type;
+ size = range_state[i].size_pfn;
+ if (type >= MTRR_NUM_TYPES)
+ continue;
+ if (!size)
+ type = MTRR_NUM_TYPES;
+ num[type]++;
+ }
+
+ /* Check if we got UC entries: */
+ if (!num[MTRR_TYPE_UNCACHABLE])
+ return 0;
+
+ /* Check if we only had WB and UC */
+ if (num[MTRR_TYPE_WRBACK] + num[MTRR_TYPE_UNCACHABLE] !=
+ num_var_ranges - num[MTRR_NUM_TYPES])
+ return 0;
+
+ return 1;
+}
+
+static unsigned long __initdata range_sums;
+
+static void __init
+mtrr_calc_range_state(u64 chunk_size, u64 gran_size,
+ unsigned long x_remove_base,
+ unsigned long x_remove_size, int i)
+{
+ /*
+ * range_new should really be an automatic variable, but
+ * putting 4096 bytes on the stack is frowned upon, to put it
+ * mildly. It is safe to make it a static __initdata variable,
+ * since mtrr_calc_range_state is only called during init and
+ * there's no way it will call itself recursively.
+ */
+ static struct range range_new[RANGE_NUM] __initdata;
+ unsigned long range_sums_new;
+ int nr_range_new;
+ int num_reg;
+
+ /* Convert ranges to var ranges state: */
+ num_reg = x86_setup_var_mtrrs(range, nr_range, chunk_size, gran_size);
+
+ /* We got new setting in range_state, check it: */
+ memset(range_new, 0, sizeof(range_new));
+ nr_range_new = x86_get_mtrr_mem_range(range_new, 0,
+ x_remove_base, x_remove_size);
+ range_sums_new = sum_ranges(range_new, nr_range_new);
+
+ result[i].chunk_sizek = chunk_size >> 10;
+ result[i].gran_sizek = gran_size >> 10;
+ result[i].num_reg = num_reg;
+
+ if (range_sums < range_sums_new) {
+ result[i].lose_cover_sizek = (range_sums_new - range_sums) << PSHIFT;
+ result[i].bad = 1;
+ } else {
+ result[i].lose_cover_sizek = (range_sums - range_sums_new) << PSHIFT;
+ }
+
+ /* Double check it: */
+ if (!result[i].bad && !result[i].lose_cover_sizek) {
+ if (nr_range_new != nr_range || memcmp(range, range_new, sizeof(range)))
+ result[i].bad = 1;
+ }
+
+ if (!result[i].bad && (range_sums - range_sums_new < min_loss_pfn[num_reg]))
+ min_loss_pfn[num_reg] = range_sums - range_sums_new;
+}
+
+static void __init mtrr_print_out_one_result(int i)
+{
+ unsigned long gran_base, chunk_base, lose_base;
+ char gran_factor, chunk_factor, lose_factor;
+
+ gran_base = to_size_factor(result[i].gran_sizek, &gran_factor);
+ chunk_base = to_size_factor(result[i].chunk_sizek, &chunk_factor);
+ lose_base = to_size_factor(result[i].lose_cover_sizek, &lose_factor);
+
+ pr_info("%sgran_size: %ld%c \tchunk_size: %ld%c \t",
+ result[i].bad ? "*BAD*" : " ",
+ gran_base, gran_factor, chunk_base, chunk_factor);
+ pr_cont("num_reg: %d \tlose cover RAM: %s%ld%c\n",
+ result[i].num_reg, result[i].bad ? "-" : "",
+ lose_base, lose_factor);
+}
+
+static int __init mtrr_search_optimal_index(void)
+{
+ int num_reg_good;
+ int index_good;
+ int i;
+
+ if (nr_mtrr_spare_reg >= num_var_ranges)
+ nr_mtrr_spare_reg = num_var_ranges - 1;
+
+ num_reg_good = -1;
+ for (i = num_var_ranges - nr_mtrr_spare_reg; i > 0; i--) {
+ if (!min_loss_pfn[i])
+ num_reg_good = i;
+ }
+
+ index_good = -1;
+ if (num_reg_good != -1) {
+ for (i = 0; i < NUM_RESULT; i++) {
+ if (!result[i].bad &&
+ result[i].num_reg == num_reg_good &&
+ !result[i].lose_cover_sizek) {
+ index_good = i;
+ break;
+ }
+ }
+ }
+
+ return index_good;
+}
+
+int __init mtrr_cleanup(unsigned address_bits)
+{
+ unsigned long x_remove_base, x_remove_size;
+ unsigned long base, size, def, dummy;
+ u64 chunk_size, gran_size;
+ mtrr_type type;
+ int index_good;
+ int i;
+
+ if (!is_cpu(INTEL) || enable_mtrr_cleanup < 1)
+ return 0;
+
+ rdmsr(MSR_MTRRdefType, def, dummy);
+ def &= 0xff;
+ if (def != MTRR_TYPE_UNCACHABLE)
+ return 0;
+
+ /* Get it and store it aside: */
+ memset(range_state, 0, sizeof(range_state));
+ for (i = 0; i < num_var_ranges; i++) {
+ mtrr_if->get(i, &base, &size, &type);
+ range_state[i].base_pfn = base;
+ range_state[i].size_pfn = size;
+ range_state[i].type = type;
+ }
+
+ /* Check if we need handle it and can handle it: */
+ if (!mtrr_need_cleanup())
+ return 0;
+
+ /* Print original var MTRRs at first, for debugging: */
+ pr_debug("original variable MTRRs\n");
+ print_out_mtrr_range_state();
+
+ memset(range, 0, sizeof(range));
+ x_remove_size = 0;
+ x_remove_base = 1 << (32 - PAGE_SHIFT);
+ if (mtrr_tom2)
+ x_remove_size = (mtrr_tom2 >> PAGE_SHIFT) - x_remove_base;
+
+ /*
+ * [0, 1M) should always be covered by var mtrr with WB
+ * and fixed mtrrs should take effect before var mtrr for it:
+ */
+ nr_range = add_range_with_merge(range, RANGE_NUM, 0, 0,
+ 1ULL<<(20 - PAGE_SHIFT));
+ /* add from var mtrr at last */
+ nr_range = x86_get_mtrr_mem_range(range, nr_range,
+ x_remove_base, x_remove_size);
+
+ range_sums = sum_ranges(range, nr_range);
+ pr_info("total RAM covered: %ldM\n",
+ range_sums >> (20 - PAGE_SHIFT));
+
+ if (mtrr_chunk_size && mtrr_gran_size) {
+ i = 0;
+ mtrr_calc_range_state(mtrr_chunk_size, mtrr_gran_size,
+ x_remove_base, x_remove_size, i);
+
+ mtrr_print_out_one_result(i);
+
+ if (!result[i].bad) {
+ set_var_mtrr_all(address_bits);
+ pr_debug("New variable MTRRs\n");
+ print_out_mtrr_range_state();
+ return 1;
+ }
+ pr_info("invalid mtrr_gran_size or mtrr_chunk_size, will find optimal one\n");
+ }
+
+ i = 0;
+ memset(min_loss_pfn, 0xff, sizeof(min_loss_pfn));
+ memset(result, 0, sizeof(result));
+ for (gran_size = (1ULL<<16); gran_size < (1ULL<<32); gran_size <<= 1) {
+
+ for (chunk_size = gran_size; chunk_size < (1ULL<<32);
+ chunk_size <<= 1) {
+
+ if (i >= NUM_RESULT)
+ continue;
+
+ mtrr_calc_range_state(chunk_size, gran_size,
+ x_remove_base, x_remove_size, i);
+ if (debug_print) {
+ mtrr_print_out_one_result(i);
+ pr_info("\n");
+ }
+
+ i++;
+ }
+ }
+
+ /* Try to find the optimal index: */
+ index_good = mtrr_search_optimal_index();
+
+ if (index_good != -1) {
+ pr_info("Found optimal setting for mtrr clean up\n");
+ i = index_good;
+ mtrr_print_out_one_result(i);
+
+ /* Convert ranges to var ranges state: */
+ chunk_size = result[i].chunk_sizek;
+ chunk_size <<= 10;
+ gran_size = result[i].gran_sizek;
+ gran_size <<= 10;
+ x86_setup_var_mtrrs(range, nr_range, chunk_size, gran_size);
+ set_var_mtrr_all(address_bits);
+ pr_debug("New variable MTRRs\n");
+ print_out_mtrr_range_state();
+ return 1;
+ } else {
+ /* print out all */
+ for (i = 0; i < NUM_RESULT; i++)
+ mtrr_print_out_one_result(i);
+ }
+
+ pr_info("mtrr_cleanup: can not find optimal value\n");
+ pr_info("please specify mtrr_gran_size/mtrr_chunk_size\n");
+
+ return 0;
+}
+#else
+int __init mtrr_cleanup(unsigned address_bits)
+{
+ return 0;
+}
+#endif
+
+static int disable_mtrr_trim;
+
+static int __init disable_mtrr_trim_setup(char *str)
+{
+ disable_mtrr_trim = 1;
+ return 0;
+}
+early_param("disable_mtrr_trim", disable_mtrr_trim_setup);
+
+/*
+ * Newer AMD K8s and later CPUs have a special magic MSR way to force WB
+ * for memory >4GB. Check for that here.
+ * Note this won't check if the MTRRs < 4GB where the magic bit doesn't
+ * apply to are wrong, but so far we don't know of any such case in the wild.
+ */
+#define Tom2Enabled (1U << 21)
+#define Tom2ForceMemTypeWB (1U << 22)
+
+int __init amd_special_default_mtrr(void)
+{
+ u32 l, h;
+
+ if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
+ boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
+ return 0;
+ if (boot_cpu_data.x86 < 0xf)
+ return 0;
+ /* In case some hypervisor doesn't pass SYSCFG through: */
+ if (rdmsr_safe(MSR_AMD64_SYSCFG, &l, &h) < 0)
+ return 0;
+ /*
+ * Memory between 4GB and top of mem is forced WB by this magic bit.
+ * Reserved before K8RevF, but should be zero there.
+ */
+ if ((l & (Tom2Enabled | Tom2ForceMemTypeWB)) ==
+ (Tom2Enabled | Tom2ForceMemTypeWB))
+ return 1;
+ return 0;
+}
+
+static u64 __init
+real_trim_memory(unsigned long start_pfn, unsigned long limit_pfn)
+{
+ u64 trim_start, trim_size;
+
+ trim_start = start_pfn;
+ trim_start <<= PAGE_SHIFT;
+
+ trim_size = limit_pfn;
+ trim_size <<= PAGE_SHIFT;
+ trim_size -= trim_start;
+
+ return e820__range_update(trim_start, trim_size, E820_TYPE_RAM, E820_TYPE_RESERVED);
+}
+
+/**
+ * mtrr_trim_uncached_memory - trim RAM not covered by MTRRs
+ * @end_pfn: ending page frame number
+ *
+ * Some buggy BIOSes don't setup the MTRRs properly for systems with certain
+ * memory configurations. This routine checks that the highest MTRR matches
+ * the end of memory, to make sure the MTRRs having a write back type cover
+ * all of the memory the kernel is intending to use. If not, it'll trim any
+ * memory off the end by adjusting end_pfn, removing it from the kernel's
+ * allocation pools, warning the user with an obnoxious message.
+ */
+int __init mtrr_trim_uncached_memory(unsigned long end_pfn)
+{
+ unsigned long i, base, size, highest_pfn = 0, def, dummy;
+ mtrr_type type;
+ u64 total_trim_size;
+ /* extra one for all 0 */
+ int num[MTRR_NUM_TYPES + 1];
+
+ /*
+ * Make sure we only trim uncachable memory on machines that
+ * support the Intel MTRR architecture:
+ */
+ if (!is_cpu(INTEL) || disable_mtrr_trim)
+ return 0;
+
+ rdmsr(MSR_MTRRdefType, def, dummy);
+ def &= 0xff;
+ if (def != MTRR_TYPE_UNCACHABLE)
+ return 0;
+
+ /* Get it and store it aside: */
+ memset(range_state, 0, sizeof(range_state));
+ for (i = 0; i < num_var_ranges; i++) {
+ mtrr_if->get(i, &base, &size, &type);
+ range_state[i].base_pfn = base;
+ range_state[i].size_pfn = size;
+ range_state[i].type = type;
+ }
+
+ /* Find highest cached pfn: */
+ for (i = 0; i < num_var_ranges; i++) {
+ type = range_state[i].type;
+ if (type != MTRR_TYPE_WRBACK)
+ continue;
+ base = range_state[i].base_pfn;
+ size = range_state[i].size_pfn;
+ if (highest_pfn < base + size)
+ highest_pfn = base + size;
+ }
+
+ /* kvm/qemu doesn't have mtrr set right, don't trim them all: */
+ if (!highest_pfn) {
+ pr_info("CPU MTRRs all blank - virtualized system.\n");
+ return 0;
+ }
+
+ /* Check entries number: */
+ memset(num, 0, sizeof(num));
+ for (i = 0; i < num_var_ranges; i++) {
+ type = range_state[i].type;
+ if (type >= MTRR_NUM_TYPES)
+ continue;
+ size = range_state[i].size_pfn;
+ if (!size)
+ type = MTRR_NUM_TYPES;
+ num[type]++;
+ }
+
+ /* No entry for WB? */
+ if (!num[MTRR_TYPE_WRBACK])
+ return 0;
+
+ /* Check if we only had WB and UC: */
+ if (num[MTRR_TYPE_WRBACK] + num[MTRR_TYPE_UNCACHABLE] !=
+ num_var_ranges - num[MTRR_NUM_TYPES])
+ return 0;
+
+ memset(range, 0, sizeof(range));
+ nr_range = 0;
+ if (mtrr_tom2) {
+ range[nr_range].start = (1ULL<<(32 - PAGE_SHIFT));
+ range[nr_range].end = mtrr_tom2 >> PAGE_SHIFT;
+ if (highest_pfn < range[nr_range].end)
+ highest_pfn = range[nr_range].end;
+ nr_range++;
+ }
+ nr_range = x86_get_mtrr_mem_range(range, nr_range, 0, 0);
+
+ /* Check the head: */
+ total_trim_size = 0;
+ if (range[0].start)
+ total_trim_size += real_trim_memory(0, range[0].start);
+
+ /* Check the holes: */
+ for (i = 0; i < nr_range - 1; i++) {
+ if (range[i].end < range[i+1].start)
+ total_trim_size += real_trim_memory(range[i].end,
+ range[i+1].start);
+ }
+
+ /* Check the top: */
+ i = nr_range - 1;
+ if (range[i].end < end_pfn)
+ total_trim_size += real_trim_memory(range[i].end,
+ end_pfn);
+
+ if (total_trim_size) {
+ pr_warn("WARNING: BIOS bug: CPU MTRRs don't cover all of memory, losing %lluMB of RAM.\n",
+ total_trim_size >> 20);
+
+ if (!changed_by_mtrr_cleanup)
+ WARN_ON(1);
+
+ pr_info("update e820 for mtrr\n");
+ e820__update_table_print();
+
+ return 1;
+ }
+
+ return 0;
+}
diff --git a/arch/x86/kernel/cpu/mtrr/cyrix.c b/arch/x86/kernel/cpu/mtrr/cyrix.c
new file mode 100644
index 000000000..ca670919b
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/cyrix.c
@@ -0,0 +1,284 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+
+#include <asm/processor-cyrix.h>
+#include <asm/processor-flags.h>
+#include <asm/mtrr.h>
+#include <asm/msr.h>
+
+#include "mtrr.h"
+
+static void
+cyrix_get_arr(unsigned int reg, unsigned long *base,
+ unsigned long *size, mtrr_type * type)
+{
+ unsigned char arr, ccr3, rcr, shift;
+ unsigned long flags;
+
+ arr = CX86_ARR_BASE + (reg << 1) + reg; /* avoid multiplication by 3 */
+
+ local_irq_save(flags);
+
+ ccr3 = getCx86(CX86_CCR3);
+ setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */
+ ((unsigned char *)base)[3] = getCx86(arr);
+ ((unsigned char *)base)[2] = getCx86(arr + 1);
+ ((unsigned char *)base)[1] = getCx86(arr + 2);
+ rcr = getCx86(CX86_RCR_BASE + reg);
+ setCx86(CX86_CCR3, ccr3); /* disable MAPEN */
+
+ local_irq_restore(flags);
+
+ shift = ((unsigned char *) base)[1] & 0x0f;
+ *base >>= PAGE_SHIFT;
+
+ /*
+ * Power of two, at least 4K on ARR0-ARR6, 256K on ARR7
+ * Note: shift==0xf means 4G, this is unsupported.
+ */
+ if (shift)
+ *size = (reg < 7 ? 0x1UL : 0x40UL) << (shift - 1);
+ else
+ *size = 0;
+
+ /* Bit 0 is Cache Enable on ARR7, Cache Disable on ARR0-ARR6 */
+ if (reg < 7) {
+ switch (rcr) {
+ case 1:
+ *type = MTRR_TYPE_UNCACHABLE;
+ break;
+ case 8:
+ *type = MTRR_TYPE_WRBACK;
+ break;
+ case 9:
+ *type = MTRR_TYPE_WRCOMB;
+ break;
+ case 24:
+ default:
+ *type = MTRR_TYPE_WRTHROUGH;
+ break;
+ }
+ } else {
+ switch (rcr) {
+ case 0:
+ *type = MTRR_TYPE_UNCACHABLE;
+ break;
+ case 8:
+ *type = MTRR_TYPE_WRCOMB;
+ break;
+ case 9:
+ *type = MTRR_TYPE_WRBACK;
+ break;
+ case 25:
+ default:
+ *type = MTRR_TYPE_WRTHROUGH;
+ break;
+ }
+ }
+}
+
+/*
+ * cyrix_get_free_region - get a free ARR.
+ *
+ * @base: the starting (base) address of the region.
+ * @size: the size (in bytes) of the region.
+ *
+ * Returns: the index of the region on success, else -1 on error.
+*/
+static int
+cyrix_get_free_region(unsigned long base, unsigned long size, int replace_reg)
+{
+ unsigned long lbase, lsize;
+ mtrr_type ltype;
+ int i;
+
+ switch (replace_reg) {
+ case 7:
+ if (size < 0x40)
+ break;
+ fallthrough;
+ case 6:
+ case 5:
+ case 4:
+ return replace_reg;
+ case 3:
+ case 2:
+ case 1:
+ case 0:
+ return replace_reg;
+ }
+ /* If we are to set up a region >32M then look at ARR7 immediately */
+ if (size > 0x2000) {
+ cyrix_get_arr(7, &lbase, &lsize, &ltype);
+ if (lsize == 0)
+ return 7;
+ /* Else try ARR0-ARR6 first */
+ } else {
+ for (i = 0; i < 7; i++) {
+ cyrix_get_arr(i, &lbase, &lsize, &ltype);
+ if (lsize == 0)
+ return i;
+ }
+ /*
+ * ARR0-ARR6 isn't free
+ * try ARR7 but its size must be at least 256K
+ */
+ cyrix_get_arr(i, &lbase, &lsize, &ltype);
+ if ((lsize == 0) && (size >= 0x40))
+ return i;
+ }
+ return -ENOSPC;
+}
+
+static u32 cr4, ccr3;
+
+static void prepare_set(void)
+{
+ u32 cr0;
+
+ /* Save value of CR4 and clear Page Global Enable (bit 7) */
+ if (boot_cpu_has(X86_FEATURE_PGE)) {
+ cr4 = __read_cr4();
+ __write_cr4(cr4 & ~X86_CR4_PGE);
+ }
+
+ /*
+ * Disable and flush caches.
+ * Note that wbinvd flushes the TLBs as a side-effect
+ */
+ cr0 = read_cr0() | X86_CR0_CD;
+ wbinvd();
+ write_cr0(cr0);
+ wbinvd();
+
+ /* Cyrix ARRs - everything else was excluded at the top */
+ ccr3 = getCx86(CX86_CCR3);
+
+ /* Cyrix ARRs - everything else was excluded at the top */
+ setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10);
+}
+
+static void post_set(void)
+{
+ /* Flush caches and TLBs */
+ wbinvd();
+
+ /* Cyrix ARRs - everything else was excluded at the top */
+ setCx86(CX86_CCR3, ccr3);
+
+ /* Enable caches */
+ write_cr0(read_cr0() & ~X86_CR0_CD);
+
+ /* Restore value of CR4 */
+ if (boot_cpu_has(X86_FEATURE_PGE))
+ __write_cr4(cr4);
+}
+
+static void cyrix_set_arr(unsigned int reg, unsigned long base,
+ unsigned long size, mtrr_type type)
+{
+ unsigned char arr, arr_type, arr_size;
+
+ arr = CX86_ARR_BASE + (reg << 1) + reg; /* avoid multiplication by 3 */
+
+ /* count down from 32M (ARR0-ARR6) or from 2G (ARR7) */
+ if (reg >= 7)
+ size >>= 6;
+
+ size &= 0x7fff; /* make sure arr_size <= 14 */
+ for (arr_size = 0; size; arr_size++, size >>= 1)
+ ;
+
+ if (reg < 7) {
+ switch (type) {
+ case MTRR_TYPE_UNCACHABLE:
+ arr_type = 1;
+ break;
+ case MTRR_TYPE_WRCOMB:
+ arr_type = 9;
+ break;
+ case MTRR_TYPE_WRTHROUGH:
+ arr_type = 24;
+ break;
+ default:
+ arr_type = 8;
+ break;
+ }
+ } else {
+ switch (type) {
+ case MTRR_TYPE_UNCACHABLE:
+ arr_type = 0;
+ break;
+ case MTRR_TYPE_WRCOMB:
+ arr_type = 8;
+ break;
+ case MTRR_TYPE_WRTHROUGH:
+ arr_type = 25;
+ break;
+ default:
+ arr_type = 9;
+ break;
+ }
+ }
+
+ prepare_set();
+
+ base <<= PAGE_SHIFT;
+ setCx86(arr + 0, ((unsigned char *)&base)[3]);
+ setCx86(arr + 1, ((unsigned char *)&base)[2]);
+ setCx86(arr + 2, (((unsigned char *)&base)[1]) | arr_size);
+ setCx86(CX86_RCR_BASE + reg, arr_type);
+
+ post_set();
+}
+
+typedef struct {
+ unsigned long base;
+ unsigned long size;
+ mtrr_type type;
+} arr_state_t;
+
+static arr_state_t arr_state[8] = {
+ {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL},
+ {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}, {0UL, 0UL, 0UL}
+};
+
+static unsigned char ccr_state[7] = { 0, 0, 0, 0, 0, 0, 0 };
+
+static void cyrix_set_all(void)
+{
+ int i;
+
+ prepare_set();
+
+ /* the CCRs are not contiguous */
+ for (i = 0; i < 4; i++)
+ setCx86(CX86_CCR0 + i, ccr_state[i]);
+ for (; i < 7; i++)
+ setCx86(CX86_CCR4 + i, ccr_state[i]);
+
+ for (i = 0; i < 8; i++) {
+ cyrix_set_arr(i, arr_state[i].base,
+ arr_state[i].size, arr_state[i].type);
+ }
+
+ post_set();
+}
+
+static const struct mtrr_ops cyrix_mtrr_ops = {
+ .vendor = X86_VENDOR_CYRIX,
+ .set_all = cyrix_set_all,
+ .set = cyrix_set_arr,
+ .get = cyrix_get_arr,
+ .get_free_region = cyrix_get_free_region,
+ .validate_add_page = generic_validate_add_page,
+ .have_wrcomb = positive_have_wrcomb,
+};
+
+int __init cyrix_init_mtrr(void)
+{
+ set_mtrr_ops(&cyrix_mtrr_ops);
+ return 0;
+}
diff --git a/arch/x86/kernel/cpu/mtrr/generic.c b/arch/x86/kernel/cpu/mtrr/generic.c
new file mode 100644
index 000000000..558108296
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/generic.c
@@ -0,0 +1,924 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * This only handles 32bit MTRR on 32bit hosts. This is strictly wrong
+ * because MTRRs can span up to 40 bits (36bits on most modern x86)
+ */
+
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+
+#include <asm/processor-flags.h>
+#include <asm/cpufeature.h>
+#include <asm/tlbflush.h>
+#include <asm/mtrr.h>
+#include <asm/msr.h>
+#include <asm/memtype.h>
+
+#include "mtrr.h"
+
+struct fixed_range_block {
+ int base_msr; /* start address of an MTRR block */
+ int ranges; /* number of MTRRs in this block */
+};
+
+static struct fixed_range_block fixed_range_blocks[] = {
+ { MSR_MTRRfix64K_00000, 1 }, /* one 64k MTRR */
+ { MSR_MTRRfix16K_80000, 2 }, /* two 16k MTRRs */
+ { MSR_MTRRfix4K_C0000, 8 }, /* eight 4k MTRRs */
+ {}
+};
+
+static unsigned long smp_changes_mask;
+static int mtrr_state_set;
+u64 mtrr_tom2;
+
+struct mtrr_state_type mtrr_state;
+EXPORT_SYMBOL_GPL(mtrr_state);
+
+/*
+ * BIOS is expected to clear MtrrFixDramModEn bit, see for example
+ * "BIOS and Kernel Developer's Guide for the AMD Athlon 64 and AMD
+ * Opteron Processors" (26094 Rev. 3.30 February 2006), section
+ * "13.2.1.2 SYSCFG Register": "The MtrrFixDramModEn bit should be set
+ * to 1 during BIOS initialization of the fixed MTRRs, then cleared to
+ * 0 for operation."
+ */
+static inline void k8_check_syscfg_dram_mod_en(void)
+{
+ u32 lo, hi;
+
+ if (!((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) &&
+ (boot_cpu_data.x86 >= 0x0f)))
+ return;
+
+ rdmsr(MSR_AMD64_SYSCFG, lo, hi);
+ if (lo & K8_MTRRFIXRANGE_DRAM_MODIFY) {
+ pr_err(FW_WARN "MTRR: CPU %u: SYSCFG[MtrrFixDramModEn]"
+ " not cleared by BIOS, clearing this bit\n",
+ smp_processor_id());
+ lo &= ~K8_MTRRFIXRANGE_DRAM_MODIFY;
+ mtrr_wrmsr(MSR_AMD64_SYSCFG, lo, hi);
+ }
+}
+
+/* Get the size of contiguous MTRR range */
+static u64 get_mtrr_size(u64 mask)
+{
+ u64 size;
+
+ mask >>= PAGE_SHIFT;
+ mask |= size_or_mask;
+ size = -mask;
+ size <<= PAGE_SHIFT;
+ return size;
+}
+
+/*
+ * Check and return the effective type for MTRR-MTRR type overlap.
+ * Returns 1 if the effective type is UNCACHEABLE, else returns 0
+ */
+static int check_type_overlap(u8 *prev, u8 *curr)
+{
+ if (*prev == MTRR_TYPE_UNCACHABLE || *curr == MTRR_TYPE_UNCACHABLE) {
+ *prev = MTRR_TYPE_UNCACHABLE;
+ *curr = MTRR_TYPE_UNCACHABLE;
+ return 1;
+ }
+
+ if ((*prev == MTRR_TYPE_WRBACK && *curr == MTRR_TYPE_WRTHROUGH) ||
+ (*prev == MTRR_TYPE_WRTHROUGH && *curr == MTRR_TYPE_WRBACK)) {
+ *prev = MTRR_TYPE_WRTHROUGH;
+ *curr = MTRR_TYPE_WRTHROUGH;
+ }
+
+ if (*prev != *curr) {
+ *prev = MTRR_TYPE_UNCACHABLE;
+ *curr = MTRR_TYPE_UNCACHABLE;
+ return 1;
+ }
+
+ return 0;
+}
+
+/**
+ * mtrr_type_lookup_fixed - look up memory type in MTRR fixed entries
+ *
+ * Return the MTRR fixed memory type of 'start'.
+ *
+ * MTRR fixed entries are divided into the following ways:
+ * 0x00000 - 0x7FFFF : This range is divided into eight 64KB sub-ranges
+ * 0x80000 - 0xBFFFF : This range is divided into sixteen 16KB sub-ranges
+ * 0xC0000 - 0xFFFFF : This range is divided into sixty-four 4KB sub-ranges
+ *
+ * Return Values:
+ * MTRR_TYPE_(type) - Matched memory type
+ * MTRR_TYPE_INVALID - Unmatched
+ */
+static u8 mtrr_type_lookup_fixed(u64 start, u64 end)
+{
+ int idx;
+
+ if (start >= 0x100000)
+ return MTRR_TYPE_INVALID;
+
+ /* 0x0 - 0x7FFFF */
+ if (start < 0x80000) {
+ idx = 0;
+ idx += (start >> 16);
+ return mtrr_state.fixed_ranges[idx];
+ /* 0x80000 - 0xBFFFF */
+ } else if (start < 0xC0000) {
+ idx = 1 * 8;
+ idx += ((start - 0x80000) >> 14);
+ return mtrr_state.fixed_ranges[idx];
+ }
+
+ /* 0xC0000 - 0xFFFFF */
+ idx = 3 * 8;
+ idx += ((start - 0xC0000) >> 12);
+ return mtrr_state.fixed_ranges[idx];
+}
+
+/**
+ * mtrr_type_lookup_variable - look up memory type in MTRR variable entries
+ *
+ * Return Value:
+ * MTRR_TYPE_(type) - Matched memory type or default memory type (unmatched)
+ *
+ * Output Arguments:
+ * repeat - Set to 1 when [start:end] spanned across MTRR range and type
+ * returned corresponds only to [start:*partial_end]. Caller has
+ * to lookup again for [*partial_end:end].
+ *
+ * uniform - Set to 1 when an MTRR covers the region uniformly, i.e. the
+ * region is fully covered by a single MTRR entry or the default
+ * type.
+ */
+static u8 mtrr_type_lookup_variable(u64 start, u64 end, u64 *partial_end,
+ int *repeat, u8 *uniform)
+{
+ int i;
+ u64 base, mask;
+ u8 prev_match, curr_match;
+
+ *repeat = 0;
+ *uniform = 1;
+
+ prev_match = MTRR_TYPE_INVALID;
+ for (i = 0; i < num_var_ranges; ++i) {
+ unsigned short start_state, end_state, inclusive;
+
+ if (!(mtrr_state.var_ranges[i].mask_lo & (1 << 11)))
+ continue;
+
+ base = (((u64)mtrr_state.var_ranges[i].base_hi) << 32) +
+ (mtrr_state.var_ranges[i].base_lo & PAGE_MASK);
+ mask = (((u64)mtrr_state.var_ranges[i].mask_hi) << 32) +
+ (mtrr_state.var_ranges[i].mask_lo & PAGE_MASK);
+
+ start_state = ((start & mask) == (base & mask));
+ end_state = ((end & mask) == (base & mask));
+ inclusive = ((start < base) && (end > base));
+
+ if ((start_state != end_state) || inclusive) {
+ /*
+ * We have start:end spanning across an MTRR.
+ * We split the region into either
+ *
+ * - start_state:1
+ * (start:mtrr_end)(mtrr_end:end)
+ * - end_state:1
+ * (start:mtrr_start)(mtrr_start:end)
+ * - inclusive:1
+ * (start:mtrr_start)(mtrr_start:mtrr_end)(mtrr_end:end)
+ *
+ * depending on kind of overlap.
+ *
+ * Return the type of the first region and a pointer
+ * to the start of next region so that caller will be
+ * advised to lookup again after having adjusted start
+ * and end.
+ *
+ * Note: This way we handle overlaps with multiple
+ * entries and the default type properly.
+ */
+ if (start_state)
+ *partial_end = base + get_mtrr_size(mask);
+ else
+ *partial_end = base;
+
+ if (unlikely(*partial_end <= start)) {
+ WARN_ON(1);
+ *partial_end = start + PAGE_SIZE;
+ }
+
+ end = *partial_end - 1; /* end is inclusive */
+ *repeat = 1;
+ *uniform = 0;
+ }
+
+ if ((start & mask) != (base & mask))
+ continue;
+
+ curr_match = mtrr_state.var_ranges[i].base_lo & 0xff;
+ if (prev_match == MTRR_TYPE_INVALID) {
+ prev_match = curr_match;
+ continue;
+ }
+
+ *uniform = 0;
+ if (check_type_overlap(&prev_match, &curr_match))
+ return curr_match;
+ }
+
+ if (prev_match != MTRR_TYPE_INVALID)
+ return prev_match;
+
+ return mtrr_state.def_type;
+}
+
+/**
+ * mtrr_type_lookup - look up memory type in MTRR
+ *
+ * Return Values:
+ * MTRR_TYPE_(type) - The effective MTRR type for the region
+ * MTRR_TYPE_INVALID - MTRR is disabled
+ *
+ * Output Argument:
+ * uniform - Set to 1 when an MTRR covers the region uniformly, i.e. the
+ * region is fully covered by a single MTRR entry or the default
+ * type.
+ */
+u8 mtrr_type_lookup(u64 start, u64 end, u8 *uniform)
+{
+ u8 type, prev_type, is_uniform = 1, dummy;
+ int repeat;
+ u64 partial_end;
+
+ /* Make end inclusive instead of exclusive */
+ end--;
+
+ if (!mtrr_state_set)
+ return MTRR_TYPE_INVALID;
+
+ if (!(mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED))
+ return MTRR_TYPE_INVALID;
+
+ /*
+ * Look up the fixed ranges first, which take priority over
+ * the variable ranges.
+ */
+ if ((start < 0x100000) &&
+ (mtrr_state.have_fixed) &&
+ (mtrr_state.enabled & MTRR_STATE_MTRR_FIXED_ENABLED)) {
+ is_uniform = 0;
+ type = mtrr_type_lookup_fixed(start, end);
+ goto out;
+ }
+
+ /*
+ * Look up the variable ranges. Look of multiple ranges matching
+ * this address and pick type as per MTRR precedence.
+ */
+ type = mtrr_type_lookup_variable(start, end, &partial_end,
+ &repeat, &is_uniform);
+
+ /*
+ * Common path is with repeat = 0.
+ * However, we can have cases where [start:end] spans across some
+ * MTRR ranges and/or the default type. Do repeated lookups for
+ * that case here.
+ */
+ while (repeat) {
+ prev_type = type;
+ start = partial_end;
+ is_uniform = 0;
+ type = mtrr_type_lookup_variable(start, end, &partial_end,
+ &repeat, &dummy);
+
+ if (check_type_overlap(&prev_type, &type))
+ goto out;
+ }
+
+ if (mtrr_tom2 && (start >= (1ULL<<32)) && (end < mtrr_tom2))
+ type = MTRR_TYPE_WRBACK;
+
+out:
+ *uniform = is_uniform;
+ return type;
+}
+
+/* Get the MSR pair relating to a var range */
+static void
+get_mtrr_var_range(unsigned int index, struct mtrr_var_range *vr)
+{
+ rdmsr(MTRRphysBase_MSR(index), vr->base_lo, vr->base_hi);
+ rdmsr(MTRRphysMask_MSR(index), vr->mask_lo, vr->mask_hi);
+}
+
+/* Fill the MSR pair relating to a var range */
+void fill_mtrr_var_range(unsigned int index,
+ u32 base_lo, u32 base_hi, u32 mask_lo, u32 mask_hi)
+{
+ struct mtrr_var_range *vr;
+
+ vr = mtrr_state.var_ranges;
+
+ vr[index].base_lo = base_lo;
+ vr[index].base_hi = base_hi;
+ vr[index].mask_lo = mask_lo;
+ vr[index].mask_hi = mask_hi;
+}
+
+static void get_fixed_ranges(mtrr_type *frs)
+{
+ unsigned int *p = (unsigned int *)frs;
+ int i;
+
+ k8_check_syscfg_dram_mod_en();
+
+ rdmsr(MSR_MTRRfix64K_00000, p[0], p[1]);
+
+ for (i = 0; i < 2; i++)
+ rdmsr(MSR_MTRRfix16K_80000 + i, p[2 + i * 2], p[3 + i * 2]);
+ for (i = 0; i < 8; i++)
+ rdmsr(MSR_MTRRfix4K_C0000 + i, p[6 + i * 2], p[7 + i * 2]);
+}
+
+void mtrr_save_fixed_ranges(void *info)
+{
+ if (boot_cpu_has(X86_FEATURE_MTRR))
+ get_fixed_ranges(mtrr_state.fixed_ranges);
+}
+
+static unsigned __initdata last_fixed_start;
+static unsigned __initdata last_fixed_end;
+static mtrr_type __initdata last_fixed_type;
+
+static void __init print_fixed_last(void)
+{
+ if (!last_fixed_end)
+ return;
+
+ pr_debug(" %05X-%05X %s\n", last_fixed_start,
+ last_fixed_end - 1, mtrr_attrib_to_str(last_fixed_type));
+
+ last_fixed_end = 0;
+}
+
+static void __init update_fixed_last(unsigned base, unsigned end,
+ mtrr_type type)
+{
+ last_fixed_start = base;
+ last_fixed_end = end;
+ last_fixed_type = type;
+}
+
+static void __init
+print_fixed(unsigned base, unsigned step, const mtrr_type *types)
+{
+ unsigned i;
+
+ for (i = 0; i < 8; ++i, ++types, base += step) {
+ if (last_fixed_end == 0) {
+ update_fixed_last(base, base + step, *types);
+ continue;
+ }
+ if (last_fixed_end == base && last_fixed_type == *types) {
+ last_fixed_end = base + step;
+ continue;
+ }
+ /* new segments: gap or different type */
+ print_fixed_last();
+ update_fixed_last(base, base + step, *types);
+ }
+}
+
+static void prepare_set(void);
+static void post_set(void);
+
+static void __init print_mtrr_state(void)
+{
+ unsigned int i;
+ int high_width;
+
+ pr_debug("MTRR default type: %s\n",
+ mtrr_attrib_to_str(mtrr_state.def_type));
+ if (mtrr_state.have_fixed) {
+ pr_debug("MTRR fixed ranges %sabled:\n",
+ ((mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED) &&
+ (mtrr_state.enabled & MTRR_STATE_MTRR_FIXED_ENABLED)) ?
+ "en" : "dis");
+ print_fixed(0x00000, 0x10000, mtrr_state.fixed_ranges + 0);
+ for (i = 0; i < 2; ++i)
+ print_fixed(0x80000 + i * 0x20000, 0x04000,
+ mtrr_state.fixed_ranges + (i + 1) * 8);
+ for (i = 0; i < 8; ++i)
+ print_fixed(0xC0000 + i * 0x08000, 0x01000,
+ mtrr_state.fixed_ranges + (i + 3) * 8);
+
+ /* tail */
+ print_fixed_last();
+ }
+ pr_debug("MTRR variable ranges %sabled:\n",
+ mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED ? "en" : "dis");
+ high_width = (__ffs64(size_or_mask) - (32 - PAGE_SHIFT) + 3) / 4;
+
+ for (i = 0; i < num_var_ranges; ++i) {
+ if (mtrr_state.var_ranges[i].mask_lo & (1 << 11))
+ pr_debug(" %u base %0*X%05X000 mask %0*X%05X000 %s\n",
+ i,
+ high_width,
+ mtrr_state.var_ranges[i].base_hi,
+ mtrr_state.var_ranges[i].base_lo >> 12,
+ high_width,
+ mtrr_state.var_ranges[i].mask_hi,
+ mtrr_state.var_ranges[i].mask_lo >> 12,
+ mtrr_attrib_to_str(mtrr_state.var_ranges[i].base_lo & 0xff));
+ else
+ pr_debug(" %u disabled\n", i);
+ }
+ if (mtrr_tom2)
+ pr_debug("TOM2: %016llx aka %lldM\n", mtrr_tom2, mtrr_tom2>>20);
+}
+
+/* PAT setup for BP. We need to go through sync steps here */
+void __init mtrr_bp_pat_init(void)
+{
+ unsigned long flags;
+
+ local_irq_save(flags);
+ prepare_set();
+
+ pat_init();
+
+ post_set();
+ local_irq_restore(flags);
+}
+
+/* Grab all of the MTRR state for this CPU into *state */
+bool __init get_mtrr_state(void)
+{
+ struct mtrr_var_range *vrs;
+ unsigned lo, dummy;
+ unsigned int i;
+
+ vrs = mtrr_state.var_ranges;
+
+ rdmsr(MSR_MTRRcap, lo, dummy);
+ mtrr_state.have_fixed = (lo >> 8) & 1;
+
+ for (i = 0; i < num_var_ranges; i++)
+ get_mtrr_var_range(i, &vrs[i]);
+ if (mtrr_state.have_fixed)
+ get_fixed_ranges(mtrr_state.fixed_ranges);
+
+ rdmsr(MSR_MTRRdefType, lo, dummy);
+ mtrr_state.def_type = (lo & 0xff);
+ mtrr_state.enabled = (lo & 0xc00) >> 10;
+
+ if (amd_special_default_mtrr()) {
+ unsigned low, high;
+
+ /* TOP_MEM2 */
+ rdmsr(MSR_K8_TOP_MEM2, low, high);
+ mtrr_tom2 = high;
+ mtrr_tom2 <<= 32;
+ mtrr_tom2 |= low;
+ mtrr_tom2 &= 0xffffff800000ULL;
+ }
+
+ print_mtrr_state();
+
+ mtrr_state_set = 1;
+
+ return !!(mtrr_state.enabled & MTRR_STATE_MTRR_ENABLED);
+}
+
+/* Some BIOS's are messed up and don't set all MTRRs the same! */
+void __init mtrr_state_warn(void)
+{
+ unsigned long mask = smp_changes_mask;
+
+ if (!mask)
+ return;
+ if (mask & MTRR_CHANGE_MASK_FIXED)
+ pr_warn("mtrr: your CPUs had inconsistent fixed MTRR settings\n");
+ if (mask & MTRR_CHANGE_MASK_VARIABLE)
+ pr_warn("mtrr: your CPUs had inconsistent variable MTRR settings\n");
+ if (mask & MTRR_CHANGE_MASK_DEFTYPE)
+ pr_warn("mtrr: your CPUs had inconsistent MTRRdefType settings\n");
+
+ pr_info("mtrr: probably your BIOS does not setup all CPUs.\n");
+ pr_info("mtrr: corrected configuration.\n");
+}
+
+/*
+ * Doesn't attempt to pass an error out to MTRR users
+ * because it's quite complicated in some cases and probably not
+ * worth it because the best error handling is to ignore it.
+ */
+void mtrr_wrmsr(unsigned msr, unsigned a, unsigned b)
+{
+ if (wrmsr_safe(msr, a, b) < 0) {
+ pr_err("MTRR: CPU %u: Writing MSR %x to %x:%x failed\n",
+ smp_processor_id(), msr, a, b);
+ }
+}
+
+/**
+ * set_fixed_range - checks & updates a fixed-range MTRR if it
+ * differs from the value it should have
+ * @msr: MSR address of the MTTR which should be checked and updated
+ * @changed: pointer which indicates whether the MTRR needed to be changed
+ * @msrwords: pointer to the MSR values which the MSR should have
+ */
+static void set_fixed_range(int msr, bool *changed, unsigned int *msrwords)
+{
+ unsigned lo, hi;
+
+ rdmsr(msr, lo, hi);
+
+ if (lo != msrwords[0] || hi != msrwords[1]) {
+ mtrr_wrmsr(msr, msrwords[0], msrwords[1]);
+ *changed = true;
+ }
+}
+
+/**
+ * generic_get_free_region - Get a free MTRR.
+ * @base: The starting (base) address of the region.
+ * @size: The size (in bytes) of the region.
+ * @replace_reg: mtrr index to be replaced; set to invalid value if none.
+ *
+ * Returns: The index of the region on success, else negative on error.
+ */
+int
+generic_get_free_region(unsigned long base, unsigned long size, int replace_reg)
+{
+ unsigned long lbase, lsize;
+ mtrr_type ltype;
+ int i, max;
+
+ max = num_var_ranges;
+ if (replace_reg >= 0 && replace_reg < max)
+ return replace_reg;
+
+ for (i = 0; i < max; ++i) {
+ mtrr_if->get(i, &lbase, &lsize, &ltype);
+ if (lsize == 0)
+ return i;
+ }
+
+ return -ENOSPC;
+}
+
+static void generic_get_mtrr(unsigned int reg, unsigned long *base,
+ unsigned long *size, mtrr_type *type)
+{
+ u32 mask_lo, mask_hi, base_lo, base_hi;
+ unsigned int hi;
+ u64 tmp, mask;
+
+ /*
+ * get_mtrr doesn't need to update mtrr_state, also it could be called
+ * from any cpu, so try to print it out directly.
+ */
+ get_cpu();
+
+ rdmsr(MTRRphysMask_MSR(reg), mask_lo, mask_hi);
+
+ if ((mask_lo & 0x800) == 0) {
+ /* Invalid (i.e. free) range */
+ *base = 0;
+ *size = 0;
+ *type = 0;
+ goto out_put_cpu;
+ }
+
+ rdmsr(MTRRphysBase_MSR(reg), base_lo, base_hi);
+
+ /* Work out the shifted address mask: */
+ tmp = (u64)mask_hi << (32 - PAGE_SHIFT) | mask_lo >> PAGE_SHIFT;
+ mask = size_or_mask | tmp;
+
+ /* Expand tmp with high bits to all 1s: */
+ hi = fls64(tmp);
+ if (hi > 0) {
+ tmp |= ~((1ULL<<(hi - 1)) - 1);
+
+ if (tmp != mask) {
+ pr_warn("mtrr: your BIOS has configured an incorrect mask, fixing it.\n");
+ add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK);
+ mask = tmp;
+ }
+ }
+
+ /*
+ * This works correctly if size is a power of two, i.e. a
+ * contiguous range:
+ */
+ *size = -mask;
+ *base = (u64)base_hi << (32 - PAGE_SHIFT) | base_lo >> PAGE_SHIFT;
+ *type = base_lo & 0xff;
+
+out_put_cpu:
+ put_cpu();
+}
+
+/**
+ * set_fixed_ranges - checks & updates the fixed-range MTRRs if they
+ * differ from the saved set
+ * @frs: pointer to fixed-range MTRR values, saved by get_fixed_ranges()
+ */
+static int set_fixed_ranges(mtrr_type *frs)
+{
+ unsigned long long *saved = (unsigned long long *)frs;
+ bool changed = false;
+ int block = -1, range;
+
+ k8_check_syscfg_dram_mod_en();
+
+ while (fixed_range_blocks[++block].ranges) {
+ for (range = 0; range < fixed_range_blocks[block].ranges; range++)
+ set_fixed_range(fixed_range_blocks[block].base_msr + range,
+ &changed, (unsigned int *)saved++);
+ }
+
+ return changed;
+}
+
+/*
+ * Set the MSR pair relating to a var range.
+ * Returns true if changes are made.
+ */
+static bool set_mtrr_var_ranges(unsigned int index, struct mtrr_var_range *vr)
+{
+ unsigned int lo, hi;
+ bool changed = false;
+
+ rdmsr(MTRRphysBase_MSR(index), lo, hi);
+ if ((vr->base_lo & 0xfffff0ffUL) != (lo & 0xfffff0ffUL)
+ || (vr->base_hi & (size_and_mask >> (32 - PAGE_SHIFT))) !=
+ (hi & (size_and_mask >> (32 - PAGE_SHIFT)))) {
+
+ mtrr_wrmsr(MTRRphysBase_MSR(index), vr->base_lo, vr->base_hi);
+ changed = true;
+ }
+
+ rdmsr(MTRRphysMask_MSR(index), lo, hi);
+
+ if ((vr->mask_lo & 0xfffff800UL) != (lo & 0xfffff800UL)
+ || (vr->mask_hi & (size_and_mask >> (32 - PAGE_SHIFT))) !=
+ (hi & (size_and_mask >> (32 - PAGE_SHIFT)))) {
+ mtrr_wrmsr(MTRRphysMask_MSR(index), vr->mask_lo, vr->mask_hi);
+ changed = true;
+ }
+ return changed;
+}
+
+static u32 deftype_lo, deftype_hi;
+
+/**
+ * set_mtrr_state - Set the MTRR state for this CPU.
+ *
+ * NOTE: The CPU must already be in a safe state for MTRR changes.
+ * RETURNS: 0 if no changes made, else a mask indicating what was changed.
+ */
+static unsigned long set_mtrr_state(void)
+{
+ unsigned long change_mask = 0;
+ unsigned int i;
+
+ for (i = 0; i < num_var_ranges; i++) {
+ if (set_mtrr_var_ranges(i, &mtrr_state.var_ranges[i]))
+ change_mask |= MTRR_CHANGE_MASK_VARIABLE;
+ }
+
+ if (mtrr_state.have_fixed && set_fixed_ranges(mtrr_state.fixed_ranges))
+ change_mask |= MTRR_CHANGE_MASK_FIXED;
+
+ /*
+ * Set_mtrr_restore restores the old value of MTRRdefType,
+ * so to set it we fiddle with the saved value:
+ */
+ if ((deftype_lo & 0xff) != mtrr_state.def_type
+ || ((deftype_lo & 0xc00) >> 10) != mtrr_state.enabled) {
+
+ deftype_lo = (deftype_lo & ~0xcff) | mtrr_state.def_type |
+ (mtrr_state.enabled << 10);
+ change_mask |= MTRR_CHANGE_MASK_DEFTYPE;
+ }
+
+ return change_mask;
+}
+
+
+static unsigned long cr4;
+static DEFINE_RAW_SPINLOCK(set_atomicity_lock);
+
+/*
+ * Since we are disabling the cache don't allow any interrupts,
+ * they would run extremely slow and would only increase the pain.
+ *
+ * The caller must ensure that local interrupts are disabled and
+ * are reenabled after post_set() has been called.
+ */
+static void prepare_set(void) __acquires(set_atomicity_lock)
+{
+ unsigned long cr0;
+
+ /*
+ * Note that this is not ideal
+ * since the cache is only flushed/disabled for this CPU while the
+ * MTRRs are changed, but changing this requires more invasive
+ * changes to the way the kernel boots
+ */
+
+ raw_spin_lock(&set_atomicity_lock);
+
+ /* Enter the no-fill (CD=1, NW=0) cache mode and flush caches. */
+ cr0 = read_cr0() | X86_CR0_CD;
+ write_cr0(cr0);
+
+ /*
+ * Cache flushing is the most time-consuming step when programming
+ * the MTRRs. Fortunately, as per the Intel Software Development
+ * Manual, we can skip it if the processor supports cache self-
+ * snooping.
+ */
+ if (!static_cpu_has(X86_FEATURE_SELFSNOOP))
+ wbinvd();
+
+ /* Save value of CR4 and clear Page Global Enable (bit 7) */
+ if (boot_cpu_has(X86_FEATURE_PGE)) {
+ cr4 = __read_cr4();
+ __write_cr4(cr4 & ~X86_CR4_PGE);
+ }
+
+ /* Flush all TLBs via a mov %cr3, %reg; mov %reg, %cr3 */
+ count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ALL);
+ flush_tlb_local();
+
+ /* Save MTRR state */
+ rdmsr(MSR_MTRRdefType, deftype_lo, deftype_hi);
+
+ /* Disable MTRRs, and set the default type to uncached */
+ mtrr_wrmsr(MSR_MTRRdefType, deftype_lo & ~0xcff, deftype_hi);
+
+ /* Again, only flush caches if we have to. */
+ if (!static_cpu_has(X86_FEATURE_SELFSNOOP))
+ wbinvd();
+}
+
+static void post_set(void) __releases(set_atomicity_lock)
+{
+ /* Flush TLBs (no need to flush caches - they are disabled) */
+ count_vm_tlb_event(NR_TLB_LOCAL_FLUSH_ALL);
+ flush_tlb_local();
+
+ /* Intel (P6) standard MTRRs */
+ mtrr_wrmsr(MSR_MTRRdefType, deftype_lo, deftype_hi);
+
+ /* Enable caches */
+ write_cr0(read_cr0() & ~X86_CR0_CD);
+
+ /* Restore value of CR4 */
+ if (boot_cpu_has(X86_FEATURE_PGE))
+ __write_cr4(cr4);
+ raw_spin_unlock(&set_atomicity_lock);
+}
+
+static void generic_set_all(void)
+{
+ unsigned long mask, count;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ prepare_set();
+
+ /* Actually set the state */
+ mask = set_mtrr_state();
+
+ /* also set PAT */
+ pat_init();
+
+ post_set();
+ local_irq_restore(flags);
+
+ /* Use the atomic bitops to update the global mask */
+ for (count = 0; count < sizeof(mask) * 8; ++count) {
+ if (mask & 0x01)
+ set_bit(count, &smp_changes_mask);
+ mask >>= 1;
+ }
+
+}
+
+/**
+ * generic_set_mtrr - set variable MTRR register on the local CPU.
+ *
+ * @reg: The register to set.
+ * @base: The base address of the region.
+ * @size: The size of the region. If this is 0 the region is disabled.
+ * @type: The type of the region.
+ *
+ * Returns nothing.
+ */
+static void generic_set_mtrr(unsigned int reg, unsigned long base,
+ unsigned long size, mtrr_type type)
+{
+ unsigned long flags;
+ struct mtrr_var_range *vr;
+
+ vr = &mtrr_state.var_ranges[reg];
+
+ local_irq_save(flags);
+ prepare_set();
+
+ if (size == 0) {
+ /*
+ * The invalid bit is kept in the mask, so we simply
+ * clear the relevant mask register to disable a range.
+ */
+ mtrr_wrmsr(MTRRphysMask_MSR(reg), 0, 0);
+ memset(vr, 0, sizeof(struct mtrr_var_range));
+ } else {
+ vr->base_lo = base << PAGE_SHIFT | type;
+ vr->base_hi = (base & size_and_mask) >> (32 - PAGE_SHIFT);
+ vr->mask_lo = -size << PAGE_SHIFT | 0x800;
+ vr->mask_hi = (-size & size_and_mask) >> (32 - PAGE_SHIFT);
+
+ mtrr_wrmsr(MTRRphysBase_MSR(reg), vr->base_lo, vr->base_hi);
+ mtrr_wrmsr(MTRRphysMask_MSR(reg), vr->mask_lo, vr->mask_hi);
+ }
+
+ post_set();
+ local_irq_restore(flags);
+}
+
+int generic_validate_add_page(unsigned long base, unsigned long size,
+ unsigned int type)
+{
+ unsigned long lbase, last;
+
+ /*
+ * For Intel PPro stepping <= 7
+ * must be 4 MiB aligned and not touch 0x70000000 -> 0x7003FFFF
+ */
+ if (is_cpu(INTEL) && boot_cpu_data.x86 == 6 &&
+ boot_cpu_data.x86_model == 1 &&
+ boot_cpu_data.x86_stepping <= 7) {
+ if (base & ((1 << (22 - PAGE_SHIFT)) - 1)) {
+ pr_warn("mtrr: base(0x%lx000) is not 4 MiB aligned\n", base);
+ return -EINVAL;
+ }
+ if (!(base + size < 0x70000 || base > 0x7003F) &&
+ (type == MTRR_TYPE_WRCOMB
+ || type == MTRR_TYPE_WRBACK)) {
+ pr_warn("mtrr: writable mtrr between 0x70000000 and 0x7003FFFF may hang the CPU.\n");
+ return -EINVAL;
+ }
+ }
+
+ /*
+ * Check upper bits of base and last are equal and lower bits are 0
+ * for base and 1 for last
+ */
+ last = base + size - 1;
+ for (lbase = base; !(lbase & 1) && (last & 1);
+ lbase = lbase >> 1, last = last >> 1)
+ ;
+ if (lbase != last) {
+ pr_warn("mtrr: base(0x%lx000) is not aligned on a size(0x%lx000) boundary\n", base, size);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int generic_have_wrcomb(void)
+{
+ unsigned long config, dummy;
+ rdmsr(MSR_MTRRcap, config, dummy);
+ return config & (1 << 10);
+}
+
+int positive_have_wrcomb(void)
+{
+ return 1;
+}
+
+/*
+ * Generic structure...
+ */
+const struct mtrr_ops generic_mtrr_ops = {
+ .use_intel_if = 1,
+ .set_all = generic_set_all,
+ .get = generic_get_mtrr,
+ .get_free_region = generic_get_free_region,
+ .set = generic_set_mtrr,
+ .validate_add_page = generic_validate_add_page,
+ .have_wrcomb = generic_have_wrcomb,
+};
diff --git a/arch/x86/kernel/cpu/mtrr/if.c b/arch/x86/kernel/cpu/mtrr/if.c
new file mode 100644
index 000000000..a5c506f6d
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/if.c
@@ -0,0 +1,425 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/capability.h>
+#include <linux/seq_file.h>
+#include <linux/uaccess.h>
+#include <linux/proc_fs.h>
+#include <linux/ctype.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+
+#define LINE_SIZE 80
+
+#include <asm/mtrr.h>
+
+#include "mtrr.h"
+
+#define FILE_FCOUNT(f) (((struct seq_file *)((f)->private_data))->private)
+
+static const char *const mtrr_strings[MTRR_NUM_TYPES] =
+{
+ "uncachable", /* 0 */
+ "write-combining", /* 1 */
+ "?", /* 2 */
+ "?", /* 3 */
+ "write-through", /* 4 */
+ "write-protect", /* 5 */
+ "write-back", /* 6 */
+};
+
+const char *mtrr_attrib_to_str(int x)
+{
+ return (x <= 6) ? mtrr_strings[x] : "?";
+}
+
+#ifdef CONFIG_PROC_FS
+
+static int
+mtrr_file_add(unsigned long base, unsigned long size,
+ unsigned int type, bool increment, struct file *file, int page)
+{
+ unsigned int *fcount = FILE_FCOUNT(file);
+ int reg, max;
+
+ max = num_var_ranges;
+ if (fcount == NULL) {
+ fcount = kcalloc(max, sizeof(*fcount), GFP_KERNEL);
+ if (!fcount)
+ return -ENOMEM;
+ FILE_FCOUNT(file) = fcount;
+ }
+ if (!page) {
+ if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1)))
+ return -EINVAL;
+ base >>= PAGE_SHIFT;
+ size >>= PAGE_SHIFT;
+ }
+ reg = mtrr_add_page(base, size, type, true);
+ if (reg >= 0)
+ ++fcount[reg];
+ return reg;
+}
+
+static int
+mtrr_file_del(unsigned long base, unsigned long size,
+ struct file *file, int page)
+{
+ unsigned int *fcount = FILE_FCOUNT(file);
+ int reg;
+
+ if (!page) {
+ if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1)))
+ return -EINVAL;
+ base >>= PAGE_SHIFT;
+ size >>= PAGE_SHIFT;
+ }
+ reg = mtrr_del_page(-1, base, size);
+ if (reg < 0)
+ return reg;
+ if (fcount == NULL)
+ return reg;
+ if (fcount[reg] < 1)
+ return -EINVAL;
+ --fcount[reg];
+ return reg;
+}
+
+/*
+ * seq_file can seek but we ignore it.
+ *
+ * Format of control line:
+ * "base=%Lx size=%Lx type=%s" or "disable=%d"
+ */
+static ssize_t
+mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos)
+{
+ int i, err;
+ unsigned long reg;
+ unsigned long long base, size;
+ char *ptr;
+ char line[LINE_SIZE];
+ int length;
+ size_t linelen;
+
+ memset(line, 0, LINE_SIZE);
+
+ len = min_t(size_t, len, LINE_SIZE - 1);
+ length = strncpy_from_user(line, buf, len);
+ if (length < 0)
+ return length;
+
+ linelen = strlen(line);
+ ptr = line + linelen - 1;
+ if (linelen && *ptr == '\n')
+ *ptr = '\0';
+
+ if (!strncmp(line, "disable=", 8)) {
+ reg = simple_strtoul(line + 8, &ptr, 0);
+ err = mtrr_del_page(reg, 0, 0);
+ if (err < 0)
+ return err;
+ return len;
+ }
+
+ if (strncmp(line, "base=", 5))
+ return -EINVAL;
+
+ base = simple_strtoull(line + 5, &ptr, 0);
+ ptr = skip_spaces(ptr);
+
+ if (strncmp(ptr, "size=", 5))
+ return -EINVAL;
+
+ size = simple_strtoull(ptr + 5, &ptr, 0);
+ if ((base & 0xfff) || (size & 0xfff))
+ return -EINVAL;
+ ptr = skip_spaces(ptr);
+
+ if (strncmp(ptr, "type=", 5))
+ return -EINVAL;
+ ptr = skip_spaces(ptr + 5);
+
+ i = match_string(mtrr_strings, MTRR_NUM_TYPES, ptr);
+ if (i < 0)
+ return i;
+
+ base >>= PAGE_SHIFT;
+ size >>= PAGE_SHIFT;
+ err = mtrr_add_page((unsigned long)base, (unsigned long)size, i, true);
+ if (err < 0)
+ return err;
+ return len;
+}
+
+static long
+mtrr_ioctl(struct file *file, unsigned int cmd, unsigned long __arg)
+{
+ int err = 0;
+ mtrr_type type;
+ unsigned long base;
+ unsigned long size;
+ struct mtrr_sentry sentry;
+ struct mtrr_gentry gentry;
+ void __user *arg = (void __user *) __arg;
+
+ memset(&gentry, 0, sizeof(gentry));
+
+ switch (cmd) {
+ case MTRRIOC_ADD_ENTRY:
+ case MTRRIOC_SET_ENTRY:
+ case MTRRIOC_DEL_ENTRY:
+ case MTRRIOC_KILL_ENTRY:
+ case MTRRIOC_ADD_PAGE_ENTRY:
+ case MTRRIOC_SET_PAGE_ENTRY:
+ case MTRRIOC_DEL_PAGE_ENTRY:
+ case MTRRIOC_KILL_PAGE_ENTRY:
+ if (copy_from_user(&sentry, arg, sizeof(sentry)))
+ return -EFAULT;
+ break;
+ case MTRRIOC_GET_ENTRY:
+ case MTRRIOC_GET_PAGE_ENTRY:
+ if (copy_from_user(&gentry, arg, sizeof(gentry)))
+ return -EFAULT;
+ break;
+#ifdef CONFIG_COMPAT
+ case MTRRIOC32_ADD_ENTRY:
+ case MTRRIOC32_SET_ENTRY:
+ case MTRRIOC32_DEL_ENTRY:
+ case MTRRIOC32_KILL_ENTRY:
+ case MTRRIOC32_ADD_PAGE_ENTRY:
+ case MTRRIOC32_SET_PAGE_ENTRY:
+ case MTRRIOC32_DEL_PAGE_ENTRY:
+ case MTRRIOC32_KILL_PAGE_ENTRY: {
+ struct mtrr_sentry32 __user *s32;
+
+ s32 = (struct mtrr_sentry32 __user *)__arg;
+ err = get_user(sentry.base, &s32->base);
+ err |= get_user(sentry.size, &s32->size);
+ err |= get_user(sentry.type, &s32->type);
+ if (err)
+ return err;
+ break;
+ }
+ case MTRRIOC32_GET_ENTRY:
+ case MTRRIOC32_GET_PAGE_ENTRY: {
+ struct mtrr_gentry32 __user *g32;
+
+ g32 = (struct mtrr_gentry32 __user *)__arg;
+ err = get_user(gentry.regnum, &g32->regnum);
+ err |= get_user(gentry.base, &g32->base);
+ err |= get_user(gentry.size, &g32->size);
+ err |= get_user(gentry.type, &g32->type);
+ if (err)
+ return err;
+ break;
+ }
+#endif
+ }
+
+ switch (cmd) {
+ default:
+ return -ENOTTY;
+ case MTRRIOC_ADD_ENTRY:
+#ifdef CONFIG_COMPAT
+ case MTRRIOC32_ADD_ENTRY:
+#endif
+ err =
+ mtrr_file_add(sentry.base, sentry.size, sentry.type, true,
+ file, 0);
+ break;
+ case MTRRIOC_SET_ENTRY:
+#ifdef CONFIG_COMPAT
+ case MTRRIOC32_SET_ENTRY:
+#endif
+ err = mtrr_add(sentry.base, sentry.size, sentry.type, false);
+ break;
+ case MTRRIOC_DEL_ENTRY:
+#ifdef CONFIG_COMPAT
+ case MTRRIOC32_DEL_ENTRY:
+#endif
+ err = mtrr_file_del(sentry.base, sentry.size, file, 0);
+ break;
+ case MTRRIOC_KILL_ENTRY:
+#ifdef CONFIG_COMPAT
+ case MTRRIOC32_KILL_ENTRY:
+#endif
+ err = mtrr_del(-1, sentry.base, sentry.size);
+ break;
+ case MTRRIOC_GET_ENTRY:
+#ifdef CONFIG_COMPAT
+ case MTRRIOC32_GET_ENTRY:
+#endif
+ if (gentry.regnum >= num_var_ranges)
+ return -EINVAL;
+ mtrr_if->get(gentry.regnum, &base, &size, &type);
+
+ /* Hide entries that go above 4GB */
+ if (base + size - 1 >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT))
+ || size >= (1UL << (8 * sizeof(gentry.size) - PAGE_SHIFT)))
+ gentry.base = gentry.size = gentry.type = 0;
+ else {
+ gentry.base = base << PAGE_SHIFT;
+ gentry.size = size << PAGE_SHIFT;
+ gentry.type = type;
+ }
+
+ break;
+ case MTRRIOC_ADD_PAGE_ENTRY:
+#ifdef CONFIG_COMPAT
+ case MTRRIOC32_ADD_PAGE_ENTRY:
+#endif
+ err =
+ mtrr_file_add(sentry.base, sentry.size, sentry.type, true,
+ file, 1);
+ break;
+ case MTRRIOC_SET_PAGE_ENTRY:
+#ifdef CONFIG_COMPAT
+ case MTRRIOC32_SET_PAGE_ENTRY:
+#endif
+ err =
+ mtrr_add_page(sentry.base, sentry.size, sentry.type, false);
+ break;
+ case MTRRIOC_DEL_PAGE_ENTRY:
+#ifdef CONFIG_COMPAT
+ case MTRRIOC32_DEL_PAGE_ENTRY:
+#endif
+ err = mtrr_file_del(sentry.base, sentry.size, file, 1);
+ break;
+ case MTRRIOC_KILL_PAGE_ENTRY:
+#ifdef CONFIG_COMPAT
+ case MTRRIOC32_KILL_PAGE_ENTRY:
+#endif
+ err = mtrr_del_page(-1, sentry.base, sentry.size);
+ break;
+ case MTRRIOC_GET_PAGE_ENTRY:
+#ifdef CONFIG_COMPAT
+ case MTRRIOC32_GET_PAGE_ENTRY:
+#endif
+ if (gentry.regnum >= num_var_ranges)
+ return -EINVAL;
+ mtrr_if->get(gentry.regnum, &base, &size, &type);
+ /* Hide entries that would overflow */
+ if (size != (__typeof__(gentry.size))size)
+ gentry.base = gentry.size = gentry.type = 0;
+ else {
+ gentry.base = base;
+ gentry.size = size;
+ gentry.type = type;
+ }
+ break;
+ }
+
+ if (err)
+ return err;
+
+ switch (cmd) {
+ case MTRRIOC_GET_ENTRY:
+ case MTRRIOC_GET_PAGE_ENTRY:
+ if (copy_to_user(arg, &gentry, sizeof(gentry)))
+ err = -EFAULT;
+ break;
+#ifdef CONFIG_COMPAT
+ case MTRRIOC32_GET_ENTRY:
+ case MTRRIOC32_GET_PAGE_ENTRY: {
+ struct mtrr_gentry32 __user *g32;
+
+ g32 = (struct mtrr_gentry32 __user *)__arg;
+ err = put_user(gentry.base, &g32->base);
+ err |= put_user(gentry.size, &g32->size);
+ err |= put_user(gentry.regnum, &g32->regnum);
+ err |= put_user(gentry.type, &g32->type);
+ break;
+ }
+#endif
+ }
+ return err;
+}
+
+static int mtrr_close(struct inode *ino, struct file *file)
+{
+ unsigned int *fcount = FILE_FCOUNT(file);
+ int i, max;
+
+ if (fcount != NULL) {
+ max = num_var_ranges;
+ for (i = 0; i < max; ++i) {
+ while (fcount[i] > 0) {
+ mtrr_del(i, 0, 0);
+ --fcount[i];
+ }
+ }
+ kfree(fcount);
+ FILE_FCOUNT(file) = NULL;
+ }
+ return single_release(ino, file);
+}
+
+static int mtrr_seq_show(struct seq_file *seq, void *offset)
+{
+ char factor;
+ int i, max;
+ mtrr_type type;
+ unsigned long base, size;
+
+ max = num_var_ranges;
+ for (i = 0; i < max; i++) {
+ mtrr_if->get(i, &base, &size, &type);
+ if (size == 0) {
+ mtrr_usage_table[i] = 0;
+ continue;
+ }
+ if (size < (0x100000 >> PAGE_SHIFT)) {
+ /* less than 1MB */
+ factor = 'K';
+ size <<= PAGE_SHIFT - 10;
+ } else {
+ factor = 'M';
+ size >>= 20 - PAGE_SHIFT;
+ }
+ /* Base can be > 32bit */
+ seq_printf(seq, "reg%02i: base=0x%06lx000 (%5luMB), size=%5lu%cB, count=%d: %s\n",
+ i, base, base >> (20 - PAGE_SHIFT),
+ size, factor,
+ mtrr_usage_table[i], mtrr_attrib_to_str(type));
+ }
+ return 0;
+}
+
+static int mtrr_open(struct inode *inode, struct file *file)
+{
+ if (!mtrr_if)
+ return -EIO;
+ if (!mtrr_if->get)
+ return -ENXIO;
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ return single_open(file, mtrr_seq_show, NULL);
+}
+
+static const struct proc_ops mtrr_proc_ops = {
+ .proc_open = mtrr_open,
+ .proc_read = seq_read,
+ .proc_lseek = seq_lseek,
+ .proc_write = mtrr_write,
+ .proc_ioctl = mtrr_ioctl,
+#ifdef CONFIG_COMPAT
+ .proc_compat_ioctl = mtrr_ioctl,
+#endif
+ .proc_release = mtrr_close,
+};
+
+static int __init mtrr_if_init(void)
+{
+ struct cpuinfo_x86 *c = &boot_cpu_data;
+
+ if ((!cpu_has(c, X86_FEATURE_MTRR)) &&
+ (!cpu_has(c, X86_FEATURE_K6_MTRR)) &&
+ (!cpu_has(c, X86_FEATURE_CYRIX_ARR)) &&
+ (!cpu_has(c, X86_FEATURE_CENTAUR_MCR)))
+ return -ENODEV;
+
+ proc_create("mtrr", S_IWUSR | S_IRUGO, NULL, &mtrr_proc_ops);
+ return 0;
+}
+arch_initcall(mtrr_if_init);
+#endif /* CONFIG_PROC_FS */
diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.c b/arch/x86/kernel/cpu/mtrr/mtrr.c
new file mode 100644
index 000000000..2746cac9d
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/mtrr.c
@@ -0,0 +1,887 @@
+/* Generic MTRR (Memory Type Range Register) driver.
+
+ Copyright (C) 1997-2000 Richard Gooch
+ Copyright (c) 2002 Patrick Mochel
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public
+ License as published by the Free Software Foundation; either
+ version 2 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with this library; if not, write to the Free
+ Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ Richard Gooch may be reached by email at rgooch@atnf.csiro.au
+ The postal address is:
+ Richard Gooch, c/o ATNF, P. O. Box 76, Epping, N.S.W., 2121, Australia.
+
+ Source: "Pentium Pro Family Developer's Manual, Volume 3:
+ Operating System Writer's Guide" (Intel document number 242692),
+ section 11.11.7
+
+ This was cleaned and made readable by Patrick Mochel <mochel@osdl.org>
+ on 6-7 March 2002.
+ Source: Intel Architecture Software Developers Manual, Volume 3:
+ System Programming Guide; Section 9.11. (1997 edition - PPro).
+*/
+
+#include <linux/types.h> /* FIXME: kvm_para.h needs this */
+
+#include <linux/stop_machine.h>
+#include <linux/kvm_para.h>
+#include <linux/uaccess.h>
+#include <linux/export.h>
+#include <linux/mutex.h>
+#include <linux/init.h>
+#include <linux/sort.h>
+#include <linux/cpu.h>
+#include <linux/pci.h>
+#include <linux/smp.h>
+#include <linux/syscore_ops.h>
+#include <linux/rcupdate.h>
+
+#include <asm/cpufeature.h>
+#include <asm/e820/api.h>
+#include <asm/mtrr.h>
+#include <asm/msr.h>
+#include <asm/memtype.h>
+
+#include "mtrr.h"
+
+/* arch_phys_wc_add returns an MTRR register index plus this offset. */
+#define MTRR_TO_PHYS_WC_OFFSET 1000
+
+u32 num_var_ranges;
+static bool __mtrr_enabled;
+
+static bool mtrr_enabled(void)
+{
+ return __mtrr_enabled;
+}
+
+unsigned int mtrr_usage_table[MTRR_MAX_VAR_RANGES];
+static DEFINE_MUTEX(mtrr_mutex);
+
+u64 size_or_mask, size_and_mask;
+static bool mtrr_aps_delayed_init;
+
+static const struct mtrr_ops *mtrr_ops[X86_VENDOR_NUM] __ro_after_init;
+
+const struct mtrr_ops *mtrr_if;
+
+static void set_mtrr(unsigned int reg, unsigned long base,
+ unsigned long size, mtrr_type type);
+
+void __init set_mtrr_ops(const struct mtrr_ops *ops)
+{
+ if (ops->vendor && ops->vendor < X86_VENDOR_NUM)
+ mtrr_ops[ops->vendor] = ops;
+}
+
+/* Returns non-zero if we have the write-combining memory type */
+static int have_wrcomb(void)
+{
+ struct pci_dev *dev;
+
+ dev = pci_get_class(PCI_CLASS_BRIDGE_HOST << 8, NULL);
+ if (dev != NULL) {
+ /*
+ * ServerWorks LE chipsets < rev 6 have problems with
+ * write-combining. Don't allow it and leave room for other
+ * chipsets to be tagged
+ */
+ if (dev->vendor == PCI_VENDOR_ID_SERVERWORKS &&
+ dev->device == PCI_DEVICE_ID_SERVERWORKS_LE &&
+ dev->revision <= 5) {
+ pr_info("Serverworks LE rev < 6 detected. Write-combining disabled.\n");
+ pci_dev_put(dev);
+ return 0;
+ }
+ /*
+ * Intel 450NX errata # 23. Non ascending cacheline evictions to
+ * write combining memory may resulting in data corruption
+ */
+ if (dev->vendor == PCI_VENDOR_ID_INTEL &&
+ dev->device == PCI_DEVICE_ID_INTEL_82451NX) {
+ pr_info("Intel 450NX MMC detected. Write-combining disabled.\n");
+ pci_dev_put(dev);
+ return 0;
+ }
+ pci_dev_put(dev);
+ }
+ return mtrr_if->have_wrcomb ? mtrr_if->have_wrcomb() : 0;
+}
+
+/* This function returns the number of variable MTRRs */
+static void __init set_num_var_ranges(void)
+{
+ unsigned long config = 0, dummy;
+
+ if (use_intel())
+ rdmsr(MSR_MTRRcap, config, dummy);
+ else if (is_cpu(AMD) || is_cpu(HYGON))
+ config = 2;
+ else if (is_cpu(CYRIX) || is_cpu(CENTAUR))
+ config = 8;
+
+ num_var_ranges = config & 0xff;
+}
+
+static void __init init_table(void)
+{
+ int i, max;
+
+ max = num_var_ranges;
+ for (i = 0; i < max; i++)
+ mtrr_usage_table[i] = 1;
+}
+
+struct set_mtrr_data {
+ unsigned long smp_base;
+ unsigned long smp_size;
+ unsigned int smp_reg;
+ mtrr_type smp_type;
+};
+
+/**
+ * mtrr_rendezvous_handler - Work done in the synchronization handler. Executed
+ * by all the CPUs.
+ * @info: pointer to mtrr configuration data
+ *
+ * Returns nothing.
+ */
+static int mtrr_rendezvous_handler(void *info)
+{
+ struct set_mtrr_data *data = info;
+
+ /*
+ * We use this same function to initialize the mtrrs during boot,
+ * resume, runtime cpu online and on an explicit request to set a
+ * specific MTRR.
+ *
+ * During boot or suspend, the state of the boot cpu's mtrrs has been
+ * saved, and we want to replicate that across all the cpus that come
+ * online (either at the end of boot or resume or during a runtime cpu
+ * online). If we're doing that, @reg is set to something special and on
+ * all the cpu's we do mtrr_if->set_all() (On the logical cpu that
+ * started the boot/resume sequence, this might be a duplicate
+ * set_all()).
+ */
+ if (data->smp_reg != ~0U) {
+ mtrr_if->set(data->smp_reg, data->smp_base,
+ data->smp_size, data->smp_type);
+ } else if (mtrr_aps_delayed_init || !cpu_online(smp_processor_id())) {
+ mtrr_if->set_all();
+ }
+ return 0;
+}
+
+static inline int types_compatible(mtrr_type type1, mtrr_type type2)
+{
+ return type1 == MTRR_TYPE_UNCACHABLE ||
+ type2 == MTRR_TYPE_UNCACHABLE ||
+ (type1 == MTRR_TYPE_WRTHROUGH && type2 == MTRR_TYPE_WRBACK) ||
+ (type1 == MTRR_TYPE_WRBACK && type2 == MTRR_TYPE_WRTHROUGH);
+}
+
+/**
+ * set_mtrr - update mtrrs on all processors
+ * @reg: mtrr in question
+ * @base: mtrr base
+ * @size: mtrr size
+ * @type: mtrr type
+ *
+ * This is kinda tricky, but fortunately, Intel spelled it out for us cleanly:
+ *
+ * 1. Queue work to do the following on all processors:
+ * 2. Disable Interrupts
+ * 3. Wait for all procs to do so
+ * 4. Enter no-fill cache mode
+ * 5. Flush caches
+ * 6. Clear PGE bit
+ * 7. Flush all TLBs
+ * 8. Disable all range registers
+ * 9. Update the MTRRs
+ * 10. Enable all range registers
+ * 11. Flush all TLBs and caches again
+ * 12. Enter normal cache mode and reenable caching
+ * 13. Set PGE
+ * 14. Wait for buddies to catch up
+ * 15. Enable interrupts.
+ *
+ * What does that mean for us? Well, stop_machine() will ensure that
+ * the rendezvous handler is started on each CPU. And in lockstep they
+ * do the state transition of disabling interrupts, updating MTRR's
+ * (the CPU vendors may each do it differently, so we call mtrr_if->set()
+ * callback and let them take care of it.) and enabling interrupts.
+ *
+ * Note that the mechanism is the same for UP systems, too; all the SMP stuff
+ * becomes nops.
+ */
+static void
+set_mtrr(unsigned int reg, unsigned long base, unsigned long size, mtrr_type type)
+{
+ struct set_mtrr_data data = { .smp_reg = reg,
+ .smp_base = base,
+ .smp_size = size,
+ .smp_type = type
+ };
+
+ stop_machine(mtrr_rendezvous_handler, &data, cpu_online_mask);
+}
+
+static void set_mtrr_cpuslocked(unsigned int reg, unsigned long base,
+ unsigned long size, mtrr_type type)
+{
+ struct set_mtrr_data data = { .smp_reg = reg,
+ .smp_base = base,
+ .smp_size = size,
+ .smp_type = type
+ };
+
+ stop_machine_cpuslocked(mtrr_rendezvous_handler, &data, cpu_online_mask);
+}
+
+static void set_mtrr_from_inactive_cpu(unsigned int reg, unsigned long base,
+ unsigned long size, mtrr_type type)
+{
+ struct set_mtrr_data data = { .smp_reg = reg,
+ .smp_base = base,
+ .smp_size = size,
+ .smp_type = type
+ };
+
+ stop_machine_from_inactive_cpu(mtrr_rendezvous_handler, &data,
+ cpu_callout_mask);
+}
+
+/**
+ * mtrr_add_page - Add a memory type region
+ * @base: Physical base address of region in pages (in units of 4 kB!)
+ * @size: Physical size of region in pages (4 kB)
+ * @type: Type of MTRR desired
+ * @increment: If this is true do usage counting on the region
+ *
+ * Memory type region registers control the caching on newer Intel and
+ * non Intel processors. This function allows drivers to request an
+ * MTRR is added. The details and hardware specifics of each processor's
+ * implementation are hidden from the caller, but nevertheless the
+ * caller should expect to need to provide a power of two size on an
+ * equivalent power of two boundary.
+ *
+ * If the region cannot be added either because all regions are in use
+ * or the CPU cannot support it a negative value is returned. On success
+ * the register number for this entry is returned, but should be treated
+ * as a cookie only.
+ *
+ * On a multiprocessor machine the changes are made to all processors.
+ * This is required on x86 by the Intel processors.
+ *
+ * The available types are
+ *
+ * %MTRR_TYPE_UNCACHABLE - No caching
+ *
+ * %MTRR_TYPE_WRBACK - Write data back in bursts whenever
+ *
+ * %MTRR_TYPE_WRCOMB - Write data back soon but allow bursts
+ *
+ * %MTRR_TYPE_WRTHROUGH - Cache reads but not writes
+ *
+ * BUGS: Needs a quiet flag for the cases where drivers do not mind
+ * failures and do not wish system log messages to be sent.
+ */
+int mtrr_add_page(unsigned long base, unsigned long size,
+ unsigned int type, bool increment)
+{
+ unsigned long lbase, lsize;
+ int i, replace, error;
+ mtrr_type ltype;
+
+ if (!mtrr_enabled())
+ return -ENXIO;
+
+ error = mtrr_if->validate_add_page(base, size, type);
+ if (error)
+ return error;
+
+ if (type >= MTRR_NUM_TYPES) {
+ pr_warn("type: %u invalid\n", type);
+ return -EINVAL;
+ }
+
+ /* If the type is WC, check that this processor supports it */
+ if ((type == MTRR_TYPE_WRCOMB) && !have_wrcomb()) {
+ pr_warn("your processor doesn't support write-combining\n");
+ return -ENOSYS;
+ }
+
+ if (!size) {
+ pr_warn("zero sized request\n");
+ return -EINVAL;
+ }
+
+ if ((base | (base + size - 1)) >>
+ (boot_cpu_data.x86_phys_bits - PAGE_SHIFT)) {
+ pr_warn("base or size exceeds the MTRR width\n");
+ return -EINVAL;
+ }
+
+ error = -EINVAL;
+ replace = -1;
+
+ /* No CPU hotplug when we change MTRR entries */
+ cpus_read_lock();
+
+ /* Search for existing MTRR */
+ mutex_lock(&mtrr_mutex);
+ for (i = 0; i < num_var_ranges; ++i) {
+ mtrr_if->get(i, &lbase, &lsize, &ltype);
+ if (!lsize || base > lbase + lsize - 1 ||
+ base + size - 1 < lbase)
+ continue;
+ /*
+ * At this point we know there is some kind of
+ * overlap/enclosure
+ */
+ if (base < lbase || base + size - 1 > lbase + lsize - 1) {
+ if (base <= lbase &&
+ base + size - 1 >= lbase + lsize - 1) {
+ /* New region encloses an existing region */
+ if (type == ltype) {
+ replace = replace == -1 ? i : -2;
+ continue;
+ } else if (types_compatible(type, ltype))
+ continue;
+ }
+ pr_warn("0x%lx000,0x%lx000 overlaps existing 0x%lx000,0x%lx000\n", base, size, lbase,
+ lsize);
+ goto out;
+ }
+ /* New region is enclosed by an existing region */
+ if (ltype != type) {
+ if (types_compatible(type, ltype))
+ continue;
+ pr_warn("type mismatch for %lx000,%lx000 old: %s new: %s\n",
+ base, size, mtrr_attrib_to_str(ltype),
+ mtrr_attrib_to_str(type));
+ goto out;
+ }
+ if (increment)
+ ++mtrr_usage_table[i];
+ error = i;
+ goto out;
+ }
+ /* Search for an empty MTRR */
+ i = mtrr_if->get_free_region(base, size, replace);
+ if (i >= 0) {
+ set_mtrr_cpuslocked(i, base, size, type);
+ if (likely(replace < 0)) {
+ mtrr_usage_table[i] = 1;
+ } else {
+ mtrr_usage_table[i] = mtrr_usage_table[replace];
+ if (increment)
+ mtrr_usage_table[i]++;
+ if (unlikely(replace != i)) {
+ set_mtrr_cpuslocked(replace, 0, 0, 0);
+ mtrr_usage_table[replace] = 0;
+ }
+ }
+ } else {
+ pr_info("no more MTRRs available\n");
+ }
+ error = i;
+ out:
+ mutex_unlock(&mtrr_mutex);
+ cpus_read_unlock();
+ return error;
+}
+
+static int mtrr_check(unsigned long base, unsigned long size)
+{
+ if ((base & (PAGE_SIZE - 1)) || (size & (PAGE_SIZE - 1))) {
+ pr_warn("size and base must be multiples of 4 kiB\n");
+ pr_debug("size: 0x%lx base: 0x%lx\n", size, base);
+ dump_stack();
+ return -1;
+ }
+ return 0;
+}
+
+/**
+ * mtrr_add - Add a memory type region
+ * @base: Physical base address of region
+ * @size: Physical size of region
+ * @type: Type of MTRR desired
+ * @increment: If this is true do usage counting on the region
+ *
+ * Memory type region registers control the caching on newer Intel and
+ * non Intel processors. This function allows drivers to request an
+ * MTRR is added. The details and hardware specifics of each processor's
+ * implementation are hidden from the caller, but nevertheless the
+ * caller should expect to need to provide a power of two size on an
+ * equivalent power of two boundary.
+ *
+ * If the region cannot be added either because all regions are in use
+ * or the CPU cannot support it a negative value is returned. On success
+ * the register number for this entry is returned, but should be treated
+ * as a cookie only.
+ *
+ * On a multiprocessor machine the changes are made to all processors.
+ * This is required on x86 by the Intel processors.
+ *
+ * The available types are
+ *
+ * %MTRR_TYPE_UNCACHABLE - No caching
+ *
+ * %MTRR_TYPE_WRBACK - Write data back in bursts whenever
+ *
+ * %MTRR_TYPE_WRCOMB - Write data back soon but allow bursts
+ *
+ * %MTRR_TYPE_WRTHROUGH - Cache reads but not writes
+ *
+ * BUGS: Needs a quiet flag for the cases where drivers do not mind
+ * failures and do not wish system log messages to be sent.
+ */
+int mtrr_add(unsigned long base, unsigned long size, unsigned int type,
+ bool increment)
+{
+ if (!mtrr_enabled())
+ return -ENODEV;
+ if (mtrr_check(base, size))
+ return -EINVAL;
+ return mtrr_add_page(base >> PAGE_SHIFT, size >> PAGE_SHIFT, type,
+ increment);
+}
+
+/**
+ * mtrr_del_page - delete a memory type region
+ * @reg: Register returned by mtrr_add
+ * @base: Physical base address
+ * @size: Size of region
+ *
+ * If register is supplied then base and size are ignored. This is
+ * how drivers should call it.
+ *
+ * Releases an MTRR region. If the usage count drops to zero the
+ * register is freed and the region returns to default state.
+ * On success the register is returned, on failure a negative error
+ * code.
+ */
+int mtrr_del_page(int reg, unsigned long base, unsigned long size)
+{
+ int i, max;
+ mtrr_type ltype;
+ unsigned long lbase, lsize;
+ int error = -EINVAL;
+
+ if (!mtrr_enabled())
+ return -ENODEV;
+
+ max = num_var_ranges;
+ /* No CPU hotplug when we change MTRR entries */
+ cpus_read_lock();
+ mutex_lock(&mtrr_mutex);
+ if (reg < 0) {
+ /* Search for existing MTRR */
+ for (i = 0; i < max; ++i) {
+ mtrr_if->get(i, &lbase, &lsize, &ltype);
+ if (lbase == base && lsize == size) {
+ reg = i;
+ break;
+ }
+ }
+ if (reg < 0) {
+ pr_debug("no MTRR for %lx000,%lx000 found\n",
+ base, size);
+ goto out;
+ }
+ }
+ if (reg >= max) {
+ pr_warn("register: %d too big\n", reg);
+ goto out;
+ }
+ mtrr_if->get(reg, &lbase, &lsize, &ltype);
+ if (lsize < 1) {
+ pr_warn("MTRR %d not used\n", reg);
+ goto out;
+ }
+ if (mtrr_usage_table[reg] < 1) {
+ pr_warn("reg: %d has count=0\n", reg);
+ goto out;
+ }
+ if (--mtrr_usage_table[reg] < 1)
+ set_mtrr_cpuslocked(reg, 0, 0, 0);
+ error = reg;
+ out:
+ mutex_unlock(&mtrr_mutex);
+ cpus_read_unlock();
+ return error;
+}
+
+/**
+ * mtrr_del - delete a memory type region
+ * @reg: Register returned by mtrr_add
+ * @base: Physical base address
+ * @size: Size of region
+ *
+ * If register is supplied then base and size are ignored. This is
+ * how drivers should call it.
+ *
+ * Releases an MTRR region. If the usage count drops to zero the
+ * register is freed and the region returns to default state.
+ * On success the register is returned, on failure a negative error
+ * code.
+ */
+int mtrr_del(int reg, unsigned long base, unsigned long size)
+{
+ if (!mtrr_enabled())
+ return -ENODEV;
+ if (mtrr_check(base, size))
+ return -EINVAL;
+ return mtrr_del_page(reg, base >> PAGE_SHIFT, size >> PAGE_SHIFT);
+}
+
+/**
+ * arch_phys_wc_add - add a WC MTRR and handle errors if PAT is unavailable
+ * @base: Physical base address
+ * @size: Size of region
+ *
+ * If PAT is available, this does nothing. If PAT is unavailable, it
+ * attempts to add a WC MTRR covering size bytes starting at base and
+ * logs an error if this fails.
+ *
+ * The called should provide a power of two size on an equivalent
+ * power of two boundary.
+ *
+ * Drivers must store the return value to pass to mtrr_del_wc_if_needed,
+ * but drivers should not try to interpret that return value.
+ */
+int arch_phys_wc_add(unsigned long base, unsigned long size)
+{
+ int ret;
+
+ if (pat_enabled() || !mtrr_enabled())
+ return 0; /* Success! (We don't need to do anything.) */
+
+ ret = mtrr_add(base, size, MTRR_TYPE_WRCOMB, true);
+ if (ret < 0) {
+ pr_warn("Failed to add WC MTRR for [%p-%p]; performance may suffer.",
+ (void *)base, (void *)(base + size - 1));
+ return ret;
+ }
+ return ret + MTRR_TO_PHYS_WC_OFFSET;
+}
+EXPORT_SYMBOL(arch_phys_wc_add);
+
+/*
+ * arch_phys_wc_del - undoes arch_phys_wc_add
+ * @handle: Return value from arch_phys_wc_add
+ *
+ * This cleans up after mtrr_add_wc_if_needed.
+ *
+ * The API guarantees that mtrr_del_wc_if_needed(error code) and
+ * mtrr_del_wc_if_needed(0) do nothing.
+ */
+void arch_phys_wc_del(int handle)
+{
+ if (handle >= 1) {
+ WARN_ON(handle < MTRR_TO_PHYS_WC_OFFSET);
+ mtrr_del(handle - MTRR_TO_PHYS_WC_OFFSET, 0, 0);
+ }
+}
+EXPORT_SYMBOL(arch_phys_wc_del);
+
+/*
+ * arch_phys_wc_index - translates arch_phys_wc_add's return value
+ * @handle: Return value from arch_phys_wc_add
+ *
+ * This will turn the return value from arch_phys_wc_add into an mtrr
+ * index suitable for debugging.
+ *
+ * Note: There is no legitimate use for this function, except possibly
+ * in printk line. Alas there is an illegitimate use in some ancient
+ * drm ioctls.
+ */
+int arch_phys_wc_index(int handle)
+{
+ if (handle < MTRR_TO_PHYS_WC_OFFSET)
+ return -1;
+ else
+ return handle - MTRR_TO_PHYS_WC_OFFSET;
+}
+EXPORT_SYMBOL_GPL(arch_phys_wc_index);
+
+/*
+ * HACK ALERT!
+ * These should be called implicitly, but we can't yet until all the initcall
+ * stuff is done...
+ */
+static void __init init_ifs(void)
+{
+#ifndef CONFIG_X86_64
+ amd_init_mtrr();
+ cyrix_init_mtrr();
+ centaur_init_mtrr();
+#endif
+}
+
+/* The suspend/resume methods are only for CPU without MTRR. CPU using generic
+ * MTRR driver doesn't require this
+ */
+struct mtrr_value {
+ mtrr_type ltype;
+ unsigned long lbase;
+ unsigned long lsize;
+};
+
+static struct mtrr_value mtrr_value[MTRR_MAX_VAR_RANGES];
+
+static int mtrr_save(void)
+{
+ int i;
+
+ for (i = 0; i < num_var_ranges; i++) {
+ mtrr_if->get(i, &mtrr_value[i].lbase,
+ &mtrr_value[i].lsize,
+ &mtrr_value[i].ltype);
+ }
+ return 0;
+}
+
+static void mtrr_restore(void)
+{
+ int i;
+
+ for (i = 0; i < num_var_ranges; i++) {
+ if (mtrr_value[i].lsize) {
+ set_mtrr(i, mtrr_value[i].lbase,
+ mtrr_value[i].lsize,
+ mtrr_value[i].ltype);
+ }
+ }
+}
+
+
+
+static struct syscore_ops mtrr_syscore_ops = {
+ .suspend = mtrr_save,
+ .resume = mtrr_restore,
+};
+
+int __initdata changed_by_mtrr_cleanup;
+
+#define SIZE_OR_MASK_BITS(n) (~((1ULL << ((n) - PAGE_SHIFT)) - 1))
+/**
+ * mtrr_bp_init - initialize mtrrs on the boot CPU
+ *
+ * This needs to be called early; before any of the other CPUs are
+ * initialized (i.e. before smp_init()).
+ *
+ */
+void __init mtrr_bp_init(void)
+{
+ u32 phys_addr;
+
+ init_ifs();
+
+ phys_addr = 32;
+
+ if (boot_cpu_has(X86_FEATURE_MTRR)) {
+ mtrr_if = &generic_mtrr_ops;
+ size_or_mask = SIZE_OR_MASK_BITS(36);
+ size_and_mask = 0x00f00000;
+ phys_addr = 36;
+
+ /*
+ * This is an AMD specific MSR, but we assume(hope?) that
+ * Intel will implement it too when they extend the address
+ * bus of the Xeon.
+ */
+ if (cpuid_eax(0x80000000) >= 0x80000008) {
+ phys_addr = cpuid_eax(0x80000008) & 0xff;
+ /* CPUID workaround for Intel 0F33/0F34 CPU */
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
+ boot_cpu_data.x86 == 0xF &&
+ boot_cpu_data.x86_model == 0x3 &&
+ (boot_cpu_data.x86_stepping == 0x3 ||
+ boot_cpu_data.x86_stepping == 0x4))
+ phys_addr = 36;
+
+ size_or_mask = SIZE_OR_MASK_BITS(phys_addr);
+ size_and_mask = ~size_or_mask & 0xfffff00000ULL;
+ } else if (boot_cpu_data.x86_vendor == X86_VENDOR_CENTAUR &&
+ boot_cpu_data.x86 == 6) {
+ /*
+ * VIA C* family have Intel style MTRRs,
+ * but don't support PAE
+ */
+ size_or_mask = SIZE_OR_MASK_BITS(32);
+ size_and_mask = 0;
+ phys_addr = 32;
+ }
+ } else {
+ switch (boot_cpu_data.x86_vendor) {
+ case X86_VENDOR_AMD:
+ if (cpu_feature_enabled(X86_FEATURE_K6_MTRR)) {
+ /* Pre-Athlon (K6) AMD CPU MTRRs */
+ mtrr_if = mtrr_ops[X86_VENDOR_AMD];
+ size_or_mask = SIZE_OR_MASK_BITS(32);
+ size_and_mask = 0;
+ }
+ break;
+ case X86_VENDOR_CENTAUR:
+ if (cpu_feature_enabled(X86_FEATURE_CENTAUR_MCR)) {
+ mtrr_if = mtrr_ops[X86_VENDOR_CENTAUR];
+ size_or_mask = SIZE_OR_MASK_BITS(32);
+ size_and_mask = 0;
+ }
+ break;
+ case X86_VENDOR_CYRIX:
+ if (cpu_feature_enabled(X86_FEATURE_CYRIX_ARR)) {
+ mtrr_if = mtrr_ops[X86_VENDOR_CYRIX];
+ size_or_mask = SIZE_OR_MASK_BITS(32);
+ size_and_mask = 0;
+ }
+ break;
+ default:
+ break;
+ }
+ }
+
+ if (mtrr_if) {
+ __mtrr_enabled = true;
+ set_num_var_ranges();
+ init_table();
+ if (use_intel()) {
+ /* BIOS may override */
+ __mtrr_enabled = get_mtrr_state();
+
+ if (mtrr_enabled())
+ mtrr_bp_pat_init();
+
+ if (mtrr_cleanup(phys_addr)) {
+ changed_by_mtrr_cleanup = 1;
+ mtrr_if->set_all();
+ }
+ }
+ }
+
+ if (!mtrr_enabled()) {
+ pr_info("Disabled\n");
+
+ /*
+ * PAT initialization relies on MTRR's rendezvous handler.
+ * Skip PAT init until the handler can initialize both
+ * features independently.
+ */
+ pat_disable("MTRRs disabled, skipping PAT initialization too.");
+ }
+}
+
+void mtrr_ap_init(void)
+{
+ if (!mtrr_enabled())
+ return;
+
+ if (!use_intel() || mtrr_aps_delayed_init)
+ return;
+
+ /*
+ * Ideally we should hold mtrr_mutex here to avoid mtrr entries
+ * changed, but this routine will be called in cpu boot time,
+ * holding the lock breaks it.
+ *
+ * This routine is called in two cases:
+ *
+ * 1. very early time of software resume, when there absolutely
+ * isn't mtrr entry changes;
+ *
+ * 2. cpu hotadd time. We let mtrr_add/del_page hold cpuhotplug
+ * lock to prevent mtrr entry changes
+ */
+ set_mtrr_from_inactive_cpu(~0U, 0, 0, 0);
+}
+
+/**
+ * mtrr_save_state - Save current fixed-range MTRR state of the first
+ * cpu in cpu_online_mask.
+ */
+void mtrr_save_state(void)
+{
+ int first_cpu;
+
+ if (!mtrr_enabled())
+ return;
+
+ first_cpu = cpumask_first(cpu_online_mask);
+ smp_call_function_single(first_cpu, mtrr_save_fixed_ranges, NULL, 1);
+}
+
+void set_mtrr_aps_delayed_init(void)
+{
+ if (!mtrr_enabled())
+ return;
+ if (!use_intel())
+ return;
+
+ mtrr_aps_delayed_init = true;
+}
+
+/*
+ * Delayed MTRR initialization for all AP's
+ */
+void mtrr_aps_init(void)
+{
+ if (!use_intel() || !mtrr_enabled())
+ return;
+
+ /*
+ * Check if someone has requested the delay of AP MTRR initialization,
+ * by doing set_mtrr_aps_delayed_init(), prior to this point. If not,
+ * then we are done.
+ */
+ if (!mtrr_aps_delayed_init)
+ return;
+
+ set_mtrr(~0U, 0, 0, 0);
+ mtrr_aps_delayed_init = false;
+}
+
+void mtrr_bp_restore(void)
+{
+ if (!use_intel() || !mtrr_enabled())
+ return;
+
+ mtrr_if->set_all();
+}
+
+static int __init mtrr_init_finialize(void)
+{
+ if (!mtrr_enabled())
+ return 0;
+
+ if (use_intel()) {
+ if (!changed_by_mtrr_cleanup)
+ mtrr_state_warn();
+ return 0;
+ }
+
+ /*
+ * The CPU has no MTRR and seems to not support SMP. They have
+ * specific drivers, we use a tricky method to support
+ * suspend/resume for them.
+ *
+ * TBD: is there any system with such CPU which supports
+ * suspend/resume? If no, we should remove the code.
+ */
+ register_syscore_ops(&mtrr_syscore_ops);
+
+ return 0;
+}
+subsys_initcall(mtrr_init_finialize);
diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.h b/arch/x86/kernel/cpu/mtrr/mtrr.h
new file mode 100644
index 000000000..2ac99e561
--- /dev/null
+++ b/arch/x86/kernel/cpu/mtrr/mtrr.h
@@ -0,0 +1,80 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * local MTRR defines.
+ */
+
+#include <linux/types.h>
+#include <linux/stddef.h>
+
+#define MTRR_CHANGE_MASK_FIXED 0x01
+#define MTRR_CHANGE_MASK_VARIABLE 0x02
+#define MTRR_CHANGE_MASK_DEFTYPE 0x04
+
+extern unsigned int mtrr_usage_table[MTRR_MAX_VAR_RANGES];
+
+struct mtrr_ops {
+ u32 vendor;
+ u32 use_intel_if;
+ void (*set)(unsigned int reg, unsigned long base,
+ unsigned long size, mtrr_type type);
+ void (*set_all)(void);
+
+ void (*get)(unsigned int reg, unsigned long *base,
+ unsigned long *size, mtrr_type *type);
+ int (*get_free_region)(unsigned long base, unsigned long size,
+ int replace_reg);
+ int (*validate_add_page)(unsigned long base, unsigned long size,
+ unsigned int type);
+ int (*have_wrcomb)(void);
+};
+
+extern int generic_get_free_region(unsigned long base, unsigned long size,
+ int replace_reg);
+extern int generic_validate_add_page(unsigned long base, unsigned long size,
+ unsigned int type);
+
+extern const struct mtrr_ops generic_mtrr_ops;
+
+extern int positive_have_wrcomb(void);
+
+/* library functions for processor-specific routines */
+struct set_mtrr_context {
+ unsigned long flags;
+ unsigned long cr4val;
+ u32 deftype_lo;
+ u32 deftype_hi;
+ u32 ccr3;
+};
+
+void set_mtrr_done(struct set_mtrr_context *ctxt);
+void set_mtrr_cache_disable(struct set_mtrr_context *ctxt);
+void set_mtrr_prepare_save(struct set_mtrr_context *ctxt);
+
+void fill_mtrr_var_range(unsigned int index,
+ u32 base_lo, u32 base_hi, u32 mask_lo, u32 mask_hi);
+bool get_mtrr_state(void);
+void mtrr_bp_pat_init(void);
+
+extern void __init set_mtrr_ops(const struct mtrr_ops *ops);
+
+extern u64 size_or_mask, size_and_mask;
+extern const struct mtrr_ops *mtrr_if;
+
+#define is_cpu(vnd) (mtrr_if && mtrr_if->vendor == X86_VENDOR_##vnd)
+#define use_intel() (mtrr_if && mtrr_if->use_intel_if == 1)
+
+extern unsigned int num_var_ranges;
+extern u64 mtrr_tom2;
+extern struct mtrr_state_type mtrr_state;
+
+void mtrr_state_warn(void);
+const char *mtrr_attrib_to_str(int x);
+void mtrr_wrmsr(unsigned, unsigned, unsigned);
+
+/* CPU specific mtrr init functions */
+int amd_init_mtrr(void);
+int cyrix_init_mtrr(void);
+int centaur_init_mtrr(void);
+
+extern int changed_by_mtrr_cleanup;
+extern int mtrr_cleanup(unsigned address_bits);